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Microbiota
Creator: Clayton Blake, Brisbane
One of the artworks at SouthBank as part of #CuriocityBrisbane. There is even a fence in there!!
Happy Fence Friday/ HFF
Luxury feeling 😊
Enjoying a beautiful morning with my best friend ever and knowing that we can eat and have a good stressfree meal is so important.
I find being aware of how our bodies work extremely interesting.
"If you think about it, we’ve always intuitively known that our brain and our gut were somehow connected – you only have to think about the butterflies you experience when you’re nervous or excited or the sudden dash to the bathroom that you might need to make before a big exam or a performance you’re feeling anxious about. Not to mention the common phrase “go with your gut” when it comes to decision-making. But are gut feelings actually real?
Well, science tells us that our brain, our gut, and our gut microbiome (the community of gut bugs living in our intestine) communicate with each other via the ‘microbiota-gut-brain axis’. This connection allows bi-directional communication, which means your gut talks to your brain and your brain talks to your gut. This all happens through their own biochemical language – messages sent via hormones, nerves and other signalling molecules. Doesn’t it just blow your mind how amazing our bodies are?
Considering this strong connection between our gut and our brain, it’s no wonder we literally feel some of our emotions in our gut, and it explains why those with IBS (irritable bowel syndrome) may notice that their symptoms worsen when they’re stressed.
Yet, many of us have become disconnected from the impact that stress and our emotions can have on our physical gut symptoms. When we experience these symptoms, we tend to consider what we are eating but not necessarily how we are eating – and both are important. In fact, our emotional state can radically impact on how we digest our food. For example, eating while we’re upset or rushing around can potentially lead to indigestion and/or bloating, as digestive processes are not prioritised when the body is churning out stress hormones.
On the other hand, it’s difficult to feel happy and content when we’re experiencing digestive problems and challenges with our gut health. Around 90% of the serotonin in our body (the substance that acts as a neurotransmitter in our brain to help us feel happy, calm and content) is made in the gut, which means that if gut health is compromised, serotonin production may also potentially be altered.
The good news is, the power to change our gut health is entirely in our hands. Our gut microbiome (the ecosystem of bacteria in our gut) changes according to what we eat. It really is quite remarkable that the bacteria in our gut can change within a few days as a result of our food choices. What we eat is that powerful!
Our gut bugs love lots of plant foods. Some of the fibres naturally present in plants act as food for our gut bacteria and when the bacteria ferment the fibre, they produce short-chain fatty acids and these nourish the cells that line our gut. However, it is important to remember that the foods that are nourishing for one person may not be nourishing for another. I’ve lost count of the number of people I’ve met who have continued to eat certain foods they have been told are “healthy”, despite their body sending them clear messages (often in the form of gut symptoms!) that these foods aren’t right for them.
When we begin to pay more attention to how we feel after we eat, we can learn how to identify our body’s messages and improve our instincts around what’s right for us and what’s not. This includes what we eat and how to take better care of ourselves, but also extends beyond that to having the clarity of mind to make important decisions and the ability to get through our daily tasks without feeling overwhelmed.
So, begin to pay more attention to how you’re left feeling after each meal. It can help to jot down what you’re eating and any symptoms you experience for a couple of weeks to help you identify any common denominators that might better serve to be avoided for a trial period of time*.
* Long-term exclusions are best guided and supported by an experienced nutrition professional to ensure how you eat each day is nutritionally complete."
www.foodmatters.com/article/the-gut-brain-axis?utm_source...
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signature of Alzheimer's which has functional repercussions on brain circuitry,
news.yale.edu/2022/11/30/swelling-along-brains-axons-may-...
Stop Alzheimers Corp
stopalzheimerstest.com/index.html
«light of new knowledge and the roots of ownership»
Microbes and Alzheimer’s Disease
content.iospress.com/articles/journal-of-alzheimers-disea...
Microbial Sequence Associated with Alzheimer’s Disease
content.iospress.com/journals/journal-of-alzheimers-disea...
young and healthy old people
www.healthyageing.eu/healthy-ageing-action
Елена Палей
Population biology
Microbiome
Commensal bacteria
www.gutmicrobiotaforhealth.com/en/about-gut-microbiota-info/
Skin in the Game
www.nature.com/articles/d41586-018-07429-3
informa
ventures.informa.com.
Мироздание и вектор времени
Естественное состояние
0:40 Когда Звёзды погаснут
Инфракрасное излучение
0:59
Шахматы как модель сознательного
Sean Carroll
( From the Big Bang to the Meaning of Life )
at 19:20 the core theory on T and time at 30:00
miracles of the natural world | Louie Schwartzberg
Alzheimer’s asana:
!Es La Microbiota,Idiota ¡ Dra.Sari Arponen, próxima lectura. #EsLaMictobiotaIdiota#microbiota #salud #healrhylifestyle ##bookstagramespaña #libros #lecturas2023 #cuerposanoá
Es la temporada de esta verdura. Bien sea al horno, hervidas o a la plancha son un excelente diurético y fuente de inulina que favorecerá una microbiota intestinal saludable. ¡Además por su textura son muy fotogénicas!
És la temporada d'aquesta verdura. Bé siga al forn, bollides o a la planxa són un excel·lent diürètic i font d'inulina que afavorirà una microbiota intestinal saludable. A més per la seua textura són molt fotogèniques!
It is the season of this vegetable. Whether baked, boiled or grilled, they are an excellent diuretic and source of inulin that will promote a healthy intestinal microbiota. Also because of their texture they are very photogenic!
#nikonD850 #tamron70200g2 #carxofa #robisa #godoxlighting #vanguardworldes #neewer #alcachofas #comidasaludable #valència #gastronomia #food #stilllife #bodegon @nikonespana_official @robisa.es @godoxlighting @neewer @vanguardworldes @natgeoesp
Some strange weather modification shenanigans went on yesterday in the area, and I've chosen a bleak looking photo as a backdrop to this description.
Upon arriving to the woods, we were greeted by a hailstorm. Nothing to write home about in and of itself but... the air temperature kept 7 degrees above the freezing point. Yet the icy pellets would not melt. This lasted for 20 minutes or so, then changed into rain, then stopped. Skies cleared, a real-life 7*C temperature returned, then another band of hail precipitation came and pelted down for 10 minutes.
These weird phenomena have been occurring for a few years now, but have recently assumed a more regular and in-your-face appearance. In January this year, after tinkering with our car, I wanted to clean my hands in the snow, the abundance of which had become unprecedented in the past half a decade. 4 degrees above the freezing point (shortly after 15 below) plus many years of experience playing with snow at various temperatures during wintertime instilled a confidence in me as to what I should be expecting in terms of texture and viscosity of the water crystals I was about to use as a cleaning agent. I was dumbfounded to discover that the "snow" I'd just scooped up from the ground would not stick or melt, it just escaped through my fingers almost like grains of sand.
Countless visits to the woods would leave me puzzled on noticing vast areas with plants suddenly withering mid-season, yet keeping their bronzed, wizened foliage even through winter. Then, leaves which did fall in autumn, failed to decompose and would just drift in an eternal layer, crumbling only below the feet of hikers. What happened to the microbiota..?
If you're more or less attuned to Nature, you know when something is off. I've been noticing things on my own and would pick bits and pieces of information from like-minded people. Then I stumbled upon Dane Wigington and GeoEngineeringWatch.org — if you haven't seen Dane's latest docu, "The Dimming," please do. It may be a shocker, an eye-opener, or it may simply provide a few missing pieces to the puzzle you might have been trying to solve.
Especially in the current global state of affairs.
There is a superhighway between the brain and GI system that holds great sway over humans
"There is a muscle that encircles the gut like a lasso when we are sitting… creating a kink in the tube," Giulia Enders explains in Gut: The Inside Story of Our Body's Most Underrated Organ. She calls the mechanism "an extra insurance policy, in addition to our old friends, the sphincters" (you have two sphincters – keep reading) and cites studies showing that squatters, with their unkinked guts, are less susceptible to haemorrhoids and constipation.Enders, a 25-year-old student at the Institute for Microbiology in Frankfurt, inside an underground public lavatory in central London. "Is there a toilet in this toilet?" she asks when she arrives. There is not, a barista tells her. The Victorian urinals, abandoned in the 1960s, have been converted into cafe with booths and stools, and no room for anything else.After a dash to a pub loo above ground, Enders talks with infectious energy about the wonder of the gut. She has been delighted to discover how many people share her fascination with a subject that can suffer for being taboo. "Even today in the taxi, I told the driver what I was doing and within about two minutes he was telling me about his constipation," she says in perfect English, which she owes to a year of study in the US. "And it's not just him. It's ladies with chic hair at big gala dinners, too. Everyone wants to talk about it."Enders first got noticed after a self-assured turn at a science slam in Berlin three years ago. Her 10-minute lecture went viral on YouTube, and now, weeks after completing her final exams as a doctoral student, she is a publishing sensation. Her book, called Darm Mit Charme ("Charming Bowels") in Germany, has sold more than 1.3 million copies since it came out last year. Rights have been sold to dozens of countries.
Her way into the gut is a lightness that some reviewers have found too childish or lacking in scientific rigour to be taken seriously. But there is something compelling and refreshing about her curiosity and popular approach. "When I read the research, I think, why don't people know about this – why am I reading about it in some paper or specialist magazine? It's ridiculous because everyone has to deal with it on a daily basis." After she explains the inspiration for her fixation (the suicide of an acquaintance who had had severe halitosis, and her own teenage skin condition, which turned out to have been caused by a wheat intolerance) Enders starts at the end of the digestive tract with what she calls the "masterly performance" that is defecation. "There is so much about the anus that we don't know," she says, reaching for a gluten-free chocolate chip cookie. "The first surprise is the sophistication of our sphincters… you know about the outer one because you can control it, but the inner one nobody knows about."
This inner opening is beyond our conscious control, releasing waste material into a sort of anal vestibule where, in Enders words, "a small taster" hits sensor cells that tell the body what it's dealing with and how to respond using the outer sphincter. This opening, and our mouths, are the recognisable and controllable ends of a system that, stretched out, would be almost as long as a bus. But it's the bits in between, and their link with the rest of our bodies, including our brains and emotions, that really interest Enders.
"Medical diagrams show the small intestine as a sausage thing chaotically going through our belly," she says. "But it is an extraordinary work of architecture that moves so harmonically when you see it during surgery. It's clean and smooth, like soft fabric, and moves like this." She performs a wavy, pulsating motion with her hands. Enders believes that if we could think differently about the gut, we might more readily understand its role beyond basic digestion – and be kinder to it. The great extent to which the gut can influence health and mood is a growing field in medicine. We speak of it all the time, whether we describe "gut feelings", "butterflies in our stomachs", or "pooing our pants" in fear, but popular understanding of this gut-brain axis remains low.
A primal connection exists between our brain and our gut. We often talk about a “gut feeling” when we meet someone for the first time. We’re told to “trust our gut instinct” when making a difficult decision or that it’s “gut check time” when faced with a situation that tests our nerve and determination. This mind-gut connection is not just metaphorical. Our brain and gut are connected by an extensive network of neurons and a highway of chemicals and hormones that constantly provide feedback about how hungry we are, whether or not we’re experiencing stress, or if we’ve ingested a disease-causing microbe. This information superhighway is called the brain-gut axis and it provides constant updates on the state of affairs at your two ends. That sinking feeling in the pit of your stomach after looking at your postholiday credit card bill is a vivid example of the brain-gut connection at work. You’re stressed and your gut knows it—immediately.
The enteric nervous system is often referred to as our body’s second brain. There are hundreds of million of neurons connecting the brain to the enteric nervous system, the part of the nervous system that is tasked with controlling the gastrointestinal system. This vast web of connections monitors the entire digestive tract from the esophagus to the anus. The enteric nervous system is so extensive that it can operate as an independent entity without input from our central nervous system, although they are in regular communication. While our “second” brain cannot compose a symphony or paint a masterpiece the way the brain in our skull can, it does perform an important role in managing the workings of our inner tube. The network of neurons in the gut is as plentiful and complex as the network of neurons in our spinal cord, which may seem overly complex just to keep track of digestion. Why is our gut the only organ in our body that needs its own “brain”? Is it just to manage the process of digestion? Or could it be that one job of our second brain is to listen in on the trillions of microbes residing in the gut?
Operations of the enteric nervous system are overseen by the brain and central nervous system. The central nervous system is in communication with the gut via the sympathetic and parasympathetic branches of the autonomic nervous system, the involuntary arm of the nervous system that controls heart rate, breathing, and digestion. The autonomic nervous system is tasked with the job of regulating the speed at which food transits through the gut, the secretion of acid in our stomach, and the production of mucus on the intestinal lining. The hypothalamic-pituitary-adrenal axis, or HPA axis, is another mechanism by which the brain can communicate with the gut to help control digestion through the action of hormones.
This circuitry of neurons, hormones, and chemical neurotransmitters not only sends messages to the brain about the status of our gut, it allows for the brain to directly impact the gut environment. The rate at which food is being moved and how much mucus is lining the gut—both of which can be controlled by the central nervous system—have a direct impact on the environmental conditions the microbiota experiences.
Like any ecosystem inhabited by competing species, the environment within the gut dictates which inhabitants thrive. Just as creatures adapted to a moist rain forest would struggle in the desert, microbes relying on the mucus layer will struggle in a gut where mucus is exceedingly sparse and thin. Bulk up the mucus, and the mucus-adapted microbes can stage a comeback. The nervous system, through its ability to affect gut transit time and mucus secretion, can help dictate which microbes inhabit the gut. In this case, even if the decisions are not conscious, it’s mind over microbes.
What about the microbial side? When the microbiota adjusts to a change in diet or to a stress-induced decrease in gut transit time, is the brain made aware of this modification? Does the brain-gut axis run in one direction only, with all signals going from brain to gut, or are some signals going the other way? Is that voice in your head that is asking for a snack coming from your mind or is it emanating from the insatiable masses in your bowels? Recent evidence indicates that not only is our brain “aware” of our gut microbes, but these bacteria can influence our perception of the world and alter our behavior. It is becoming clear that the influence of our microbiota reaches far beyond the gut to affect an aspect of our biology few would have predicted—our mind.
For example, the gut microbiota influences the body’s level of the potent neurotransmitter serotonin, which regulates feelings of happiness. Some of the most prescribed drugs in the U.S. for treating anxiety and depression, like Prozac, Zoloft, and Paxil, work by modulating levels of serotonin. And serotonin is likely just one of a numerous biochemical messengers dictating our mood and behavior that the microbiota impacts.
Most of us can relate to the experience of having butterflies in our stomach, or to a visceral gut-wrenching feeling, and how often are we told not to ignore our “gut-instinct” or “gut-feeling” when making a decision.
Even from our simple slang, it’s clear just how symbolically connected the gut is to our emotions. Now, there’s tangible proof to support these popular metaphors.
We all have a microbiome, and they are as unique as our neural pathways
Research has shown that the body is actually composed of more bacteria than cells. We are more bug than human! Collectively, these trillions of bacteria are called the microbiome. Most of those bacteria reside in our gut, sometimes referred to as the gut microbiota, and they play multiple roles in our overall health.
The gut is no longer seen as an entity with the sole purpose of helping with all aspects of digestion. It’s also being considered as a key player in regulating inflammation and immunity.
A healthy gut consists of different iterations of bacteria for different people, and this diversity maintains wellness. A shift away from “normal” gut microbiota diversity is called dysbiosis, and dysbiosis may contribute to disease. In light of this, the microbiome has become the focus of much research attention as a new way of understanding autoimmune, gastrointestinal, and even brain disorders.
The benefit of a healthy gut is illustrated most effectively during early development. Research has indicated just how sensitive a fetus is to any changes in a mother’s microbiotic makeup, so much so that it can alter the way a baby’s brain develops. If a baby is born via cesarean section, it misses an opportunity to ingest the mother’s bacteria as it travels down the vaginal canal. Studies show that those born via c-section have to work to regain the same diversity in their microbiome as those born vaginally. Throughout our lives, our microbiome continues to be a vulnerable entity, and as we are exposed to stress, toxins, chemicals, certain diets, and even exercise, our microbiome fluctuates for better or worse.
The gut as second brain
Our gut microbiota play a vital role in our physical and psychological health via its own neural network: the enteric nervous system (ENS), a complex system of about 100 million nerves found in the lining of the gut.
The ENS is sometimes called the “second brain,” and it actually arises from the same tissues as our central nervous system (CNS) during fetal development. Therefore, it has many structural and chemical parallels to the brain.
Our ENS doesn’t wax philosophical or make executive decisions like the gray shiny mound in our skulls. Yet, in a miraculously orchestrated symphony of hormones, neurotransmitters, and electrical impulses through a pathway of nerves, both “brains” communicate back and forth. These pathways include and involve endocrine, immune, and neural pathways.
At this point in time, even though the research is inchoate and complex, it is clear that the brain and gut are so intimately connected that it sometimes seems like one system, not two.
Our emotions play a big role in functional gastrointestinal disorders
Given how closely the gut and brain interact, it has become clear that emotional and psychosocial factors can trigger symptoms in the gut. This is especially true in cases when the gut is acting up and there’s no obvious physical cause.
The functional gastrointestinal disorders (FGIDs) are a group of more than 20 chronic and hard to treat medical conditions of the gastrointestinal tract that constitute a large proportion of the presenting problems seen in clinical gastroenterology.
While FGID’s were once thought to be partly “in one’s head,” a more precise conceptualization of these difficulties posits that psychosocial factors influence the actual physiology of the gut, as well as the modulation of symptoms. In other words, psychological factors can literally impact upon physical factors, like the movement and contractions of the GI tract, causing, inflammation, pain, and other bowel symptoms.
Mental health impacts gut wellness
In light of this new understanding, it might be impossible to heal FGID’s without considering the impact of stress and emotion. Studies have shown that patients who tried psychologically based approaches had greater improvement in their symptoms compared with patients who received conventional medical treatment.
Along those lines, a new pilot study from Harvard University affiliates Benson-Henry Institute for Mind Body Medicine at Massachusetts General Hospital and Beth Israel Deaconess Medical Center found that meditation could have a significant impact for those with irritable bowel syndrome and inflammatory bowel disease. Forty-eight patients with either IBS or IBD took a 9-week session that included meditation training, and the results showed reduced pain, improved symptoms, stress reduction, and the change in expression of genes that contribute to inflammation.
Poor gut health can lead to neurological and neuropsychiatric disorders
Vice-versa, poor gut health has been implicated in neurological and neuropsychiatric disorders. Disturbances in gut health have been linked to multiple sclerosis, autistic spectrum disorders, and Parkinson’s disease. This is potentially related to pro-inflammatory states elicited by gut dysbiosis-microbial imbalance on or inside the body. Additional connections between age-related gut changes and Alzheimer’s disease have also been made.
Further, there is now research that is dubbing depression as an inflammatory disorder mediated by poor gut health. In fact, multiple animal studies have shown that manipulating the gut microbiota in some way can produce behaviors related to anxiety and depression. (Maes, Kubera, Leunis, Berk, J. Affective Disorders, 2012 and Berk, Williams, Jacka, BMC Med, 2013).
Our brain’s health, which will be discussed in more depth in a later blog post, is dependent on many lifestyle choices that mediate gut health; including most notably diet (i.e., reduction of excess sugar and refined carbohydrates) and pre and probiotic intake.
The brain-gut connection has treatment implications
We are now faced with the possibility of both prevention and treatment of neurological/neuropsychiatric difficulties via proper gut health. On the flip side, stress-reduction and other psychological treatments can help prevent and treat gastrointestinal disorders. This discovery can potentially lead to reduced morbidity, impairment, and chronic dependency on health care resources.
The most empowering aspect to the gut-brain connection is the understanding that many of our daily lifestyle choices play a role in mediating our overall wellness. This whole-body approach to healthcare and wellness continues to show its value in our longevity, well-being, and quality of life: that both physical and mental health go hand-in-hand.
The one year mission to the International Space Station came to a successful end with the return of NASA astronaut Scott Kelly and Roscosmos cosmonaut Mikhail Kornienko on March 1. Before the Soyuz capsule unberthed from the station to return them to Earth, Kelly performed some final human research investigations that could benefit people that live and work in extreme environments both in space and on Earth.
One of those tasks was coordinating Kelly's last blood draw in microgravity for the Microbiome investigation. The NASA study investigates the impact of space travel on both the human immune system and an individual’s microbiome -- the collection of microbes living in and on the human body at any given time. To monitor the status of the crew members' microbiome and immune system and their interaction with the unique environment of the orbiting laboratory, periodic samples are taken from different parts of the body and the surfaces around the interior of the station, such as exercise equipment, sleeping quarters or the food preparation area. The blood taken right before closing the hatch will be compared to blood drawn before Kelly left for space a year ago, other samples taken while he was on the station, and more blood that will be drawn after he has been back on Earth for several weeks.
This study will determine if anything changes the microbiome because of extreme environments and the related human health risk. Scientists will learn more about how the body changes during long-duration missions and how the body recovers from extended exposure to the microgravity environment. Other potential applications could be to further research in preliminary detection of diseases, alterations in metabolic function, and immune system deficiency.
The blood drawn over the course of the past year is also part of the Twins Study series of investigations. The integrated compilation of 10 different studies at multiple research centers takes advantage of the unique opportunity of studying the effects of space travel on identical twins Scott Kelly and his brother -- former astronaut Mark Kelly.
Identical twins are genetically almost the same, so studying them provides scientists a unique opportunity to examine how environment, diet, stress and other outside factors affect human health and performance. Researchers are studying changes related to the fields of genetics, psychology, physiology, microbiology and immunology. Results could be used to develop new treatments for stress-related health risks on Earth.
While Kelly wrapped up his human research investigations on the station, ESA (European Space Agency) astronaut Tim Peake began a new round of research on the astronaut immune system with JAXA's (Japan Aerospace Exploration Agency) Multi-Omics study.
Scientists believe living on the space station can cause changes in the immune system of crew members. Recent studies indicated an imbalance of the microbiota in the digestive tract, possibly caused by environmental stresses, could be the root cause. The Multi-Omics analysis could identify bacterial or metabolic clues about changes in the gut that may be reducing the effectiveness of the immune system. Peake prepared a series of biomarkers to start the 28-day session of Multi-Omics. The biomarker test kit could be used to evaluate the immune system and manage the health of astronauts during space voyages as well as be applied to life sciences technology on Earth.
Pears are considered a healthy addition to a balanced diet due to their rich nutritional profile and various health benefits. Here are some key reasons why pears are healthy:
Nutritional Content
Pears are a good source of essential vitamins and minerals, including vitamin C, vitamin K, copper, potassium, and fiber. They also contain antioxidants such as flavonoids, polyphenols, and anthocyanins.
Gut Health
Pears are high in dietary fiber, which includes both soluble and insoluble fiber. This fiber helps in maintaining healthy gut microbiota, preventing constipation, and supporting regular bowel movements. The fiber content, particularly pectin, aids in softening and adding bulk to stool.
Blood Sugar Management
Pears have a low glycemic index, which means they do not cause a rapid spike in blood sugar levels. The high fiber content in pears helps slow down the absorption of sugar, making them beneficial for managing and reducing the risk of Type 2 diabetes.
Heart Health
The potassium in pears helps lower blood pressure by improving blood flow and reducing the risk of heart disease. Flavonoids and other antioxidants in pears also contribute to reducing inflammation and improving cardiovascular health, lowering the risk of stroke and heart disease.
Bone Health
Pears contain minerals such as copper, calcium, phosphorus, manganese, magnesium, and boron, which are essential for bone health and can help reduce the risk of osteoporosis.
Weight Management
Pears are low in calories and high in fiber and water content, which helps keep you feeling full and can aid in weight management. Studies have shown that adding fruits like pears to the diet can reduce energy consumption and body weight over time.
Kidney Health
The low sodium content in pears can help prevent kidney disease by aiding in the balance of sodium and water in the body. Additionally, the malic acid in pears may help protect against kidney stones.
Antioxidant Properties
Pears are rich in antioxidants, including vitamin C, vitamin K, and copper, which help protect against oxidative damage and free radicals. These antioxidants can contribute to reducing the risk of various diseases, including cancer and other inflammatory conditions.
Overall, incorporating pears into your diet can provide a range of health benefits due to their nutrient-dense profile and various bioactive compounds.
Baer's pochard (Aythya baeri) is a diving duck found in eastern Asia. It is a resident bird in North and Central China, formerly bred in southeast Russia and Northeast China, migrating in winter to southern China, Vietnam, Japan, and India. Baer's pochard is a monotypic species. The holotype was collected in middle Amur.
It has a distinctive black head and neck with green gloss not present elsewhere in Aythya. While in poor light, it is likely to look completely black. It is very similar and closely related to the ferruginous duck, and they were previously considered to be a single species; Baer's pochard is differentiated by its white flanks when floating on the water, as well as its larger size and longer, more rounded head.
Its breeding season varies by latitude and environment. The nest, built from sedges, reeds and other plants, is placed among emergent vegetation, usually in shallow water or on small islands or ridges. Its clutch size ranges from 5 to 14. Males usually take on sentry duty, and females take on the responsibility of incubating.
Baer's pochard was once a common species in its range, but is now very rare. The number of mature individuals may be less than 1,000, and its population is still declining. Hunting and habitat loss are considered to be the main reasons. This species has been classified as critically endangered by the IUCN, and listed as a first-class protected animal in China.
Taxonomy
Baer's pochard was first scientifically described in 1863 as Anas baeri by Gustav Radde in his book Reisen im Süden von Ost-Sibirien. The epithet and English common name commemorate the Baltic German naturalist Karl Ernst von Baer. It is also called eastern white-eye, Siberian white-eye, Baer's white-eye and green-headed pochard. The holotype was collected from a small flock in middle Amur during the breeding season. In 1929, when British ornithologist E. C. Stuart Baker studied the birds of British India, he treated Baer's pochard and ferruginous duck as conspecific. However, Chinese ornithologist Tso-hsin Cheng treated them as two distinct species, as they had breeding grounds which did not overlap, and he had seen no evidence of hybridisation. While the species was long thought to have arisen from eastern populations of the ferruginous duck, American ornithologist Paul Johnsgard says its behaviors suggest it may instead be more closely related to the hardhead.
American ornithologist Bradley Curtis Livezey published a phylogenetic study based on morphological data in 1996, in which he proposed his view on the relationship among Tribe Aythyini. Baer's pochard, ferruginous duck, hardhead and Madagascar pochard are classified in subgenus Nyroca (the "white-eyes"), intrasubgenus relationship is unclear, but the ferruginous duck was suggested to be the sister group of Baer's pochard. The subgenus Aythya (the "scapu", including New Zealand Scaup, ring-necked duck, tufted duck, greater scaup and lesser scaup) is the sister group of subgenus Nyroca. The subgenus Aristonetta (the "redheads", including the common pochard, canvasback and redhead) is the sister group of all other pochards.
Two molecular phylogenetic studies on Anseriformes or Anatidae were published in 2000s, some mitochondrial genes were sequenced, but Baer's pochard was absent in both of them. The mitochondrial genome of Baer's pochard was sequenced and published in 2021. Molecular phylogenetic studies determined the relationships among Baer's pochard and other closely related species:
Tribe. Aythyini
Aythya
Baer's pochard Aythya baeri
Tufted Duck A. fuligula
Common pochard A. ferina
Redhead A. americana
Netta
Red-crested pochard Netta rufina
Asarcornis
White-winged duck Asarcornis scutulata
Description
The Baer's pochard is 41–47 cm (16–19 in) long with a 70–79 cm (28–31 in) wingspan. The male is slightly larger, weighing on average 500–730 g (18–26 oz), wings lengthed 18.6–20.3 cm (7.3–8.0 in), tail at 53–60 mm (2.1–2.4 in), and culmen at 38–44 mm (1.5–1.7 in). Relatively, the female weighing on average 590–655 g (20.8–23.1 oz), wings lengthed 19.1–20.5 cm (7.5–8.1 in), tail at 51–64 mm (2.0–2.5 in), and culmen at 40–44 mm (1.6–1.7 in). Both male and female's tarsometatarsus lengthed 33–34.7 mm (1.30–1.37 in).
Breeding male has a black head and neck with green gloss, white or paler yellow eyes, blackish-brown back, dark chestnut breast, white or light chestnut flanks and a short and low tail. The green gloss on its head is unique among Aythya. While it is likely to look completely black in poor light. Female has a dark brown head and neck that blend into the chestnut-brown breast and flanks. Eclipse and first-winter male resembles female, but retain the white eyes, while female has brown eyes. Both male and female have wide white speculum feathers, white vent-side, dark-grey bill, black nail and dark-grey tarsometatarsus.
It is similar to its close relative, the ferruginous duck (A. nyroca), both have white vent-side and iris in males, black nail, and wide white speculum feathers. Although Baer's pochard is bigger, has a longer head, body and bill. Unlike the ferruginous duck's tall and triangular head, Baer's pochard has a more rounded head and a flatter forehead. The white part on the belly extends to its flanks in Baer's pochard, which is visible when floating on the water, while the ferruginous duck has a smaller white part on its belly. The female Baer's pochard has a distinctly bright chestnut spot at the lore, which is absent in ferruginous duck.
Baer's pochard is usually a quieter duck, but during its courtship display, both sexes give harsh graaaak. Females may give kura kura kura and males may give kuro kuro at other times.
Distribution
Baer's pochard traditionally bred in the Amur and Ussuri basins in Northeast China and the southeastern Russian Far East. In recent years, it has also colonised North China and Central China. It winters in most areas south of the Yellow River in China, Taiwan, Japan, Bangladesh, India, North Korea, Laos, Myanmar, Nepal, Thailand and Vietnam, and occasionally appears in Bhutan, South Korea, Philippines or Pakistan as a rare vagrant. It leaves its wintering grounds by mid-March and returns to them by mid-October or early November.
The species has become extremely rare in its traditional breeding areas, and since 2010, there have been no confirmed breeding reports in all sites north of Beijing. However, the numbers recorded during the breeding season are smaller than those recorded in winter, so there may still be unknown breeding sites. For example, there are some doubtful breeding reports in the Chinese part of Lake Khanka, the Russian part of Lake Khasan, and the Muraviovka Park [ru]. Since 2012, new breeding sites have been discovered in several provinces of China, including Hebei, Hubei and Jiangxi; the latter two cities are far from traditional breeding sites in the Amur and Ussuri basins.[1] In these new breeding areas, warmer climate conditions provide a longer breeding season (about twice as long as in the Amur and Ussuri basins) which allows birds to lay a replacement clutch if their first clutch fails. Baer's pochard is no longer migratory in central and eastern China.
The wintering grounds have also contracted significantly in recent years. Since at least the winter of 2010-2011, Baer's pochard no longer winters in any site outside mainland China, except as a vagrant. In its wintering grounds in mainland China, the population has also declined severely, by more than 99%.
Behaviour and ecology
Baer's pochard is a shy species, that inhabit open, slow-flowing lakes, swamps and ponds. It breeds around lakes with rich aquatic vegetation, nesting in dense grass, flooded tussock meadows, or flooded shrubby meadows. In winter, it forms large flocks on large and open freshwater lakes and reservoirs with other pochards. It has strong wings, and can flyor walk at high speeds. It is also good at diving and swimming, and can quickly take off from the water when threatened or disturbed. In migrating season, they form small groups of more than 10 or dozens of birds, flying at low altitudes in wedge-shaped formations. During winter, Baer's pochard sleeps during the day, leaves for unknown feeding sites with other ducks in the dusk, and returns before dawn. Little is known about their diet beyond aquatic plants, grass seeds and molluscs.
Breeding
Baer's pochard appears to have a monogamous mating system, at least within a breeding season. In traditional breeding grounds in northeastern China, Baer's pochard gathers in gaps in the ice before it completely thawed. After the ice season, it gathers on the large, open lakes. They breed from mid-to-late May. While in Fuhe Wetland in Wuhan, Hubei, Baer's pochard gathers in large groups on the open lakes before breeding season. It is divided into small groups in mid-April, in which they will courting and mating. During courtship, the male swims around the female, repeatedly nods his head up and down. When other males approach, it swims toward them quickly to drive them away, but there is no violent fight between them. The female also nods her head in response. When the male approaches, the female straightens her neck and lowers her head to the water. He then climbs onto her body and bites her nape feathers to mate. After the mating, the male and female leave the flock for nesting.
Baer's pochard's nest is circular cylindrical, located among emergent vegetation, usually in shallow water or on small islands or ridges. The nest is made of sedges, reeds and other plants collected from the immediate vicinity, lined with a layer of down. Its clutch ranged from 5 to 14, with an average of 9.7. Males usually take on sentry duty at about 10 meters from the nest during hatching. Females leave the nest to forage 2–3 times a day, usually during 6:00-20:00, and lasted for 27–240 min. They cover the eggs with nest materials during forging, and place them onto their back when coming back. If water levels are elevated by heavy rainfall or human activity, females increase the height of the nest to avoid flooding. During the hottest days, females often stand on the nest and shelter eggs from the strong sunlight, whilst allowing circulation of air around them. Females also take water into their plumage and use it to cool the eggs. The incubation lasted for 23-26 days.
Studies have shown that the nest survival rate[note 3] of Baer's pochards is about 14–45%, and each clutch may lose one to nine eggs. About 20-30% of eggs hatched successfully, and 3–16 young fledged per nest. There are three major reasons contributing to the failure, including nest desertion (abandoned by parents), nest predation (mainly by Siberian Weasels) and flooding. The proportion of these causes varies among years. In addition, most of the breeding sites in Wuhan are Crayfish farms, the farming work and eggs collection may also be hindrances.
Biological interaction
Incomplete inter- and intra-specific brood parasitism were found in Baer's pochard. In Xianghai National Nature Reserve [zh], Baer's pochards could parasitize gadwall and common pochard, and may be parasitized by common pochard. In Wuhan, Baer's pochard shares breeding sites with cotton teal, eastern spot-billed duck and mallard. Interspecific brood parasitism was not observed. Intraspecific parasitic was found in Wuhan. If caught, the parasite will get attacked by the host.
Baer's pochard has hybridized with lesser scaup, common pochard, ferruginous duck, New Zealand scaup, chestnut teal and wood duck in captivity. Ferruginous duck was observed displaying to Baer's pochards several times in China and South Korea. Some individuals showed mixed characteristics of common, ferruginous and Baer's pochards, so they may be currently hybridising in the wild. The Baer's pochard has declined sharply in recent years, but the ferruginous and common pochard has expanded their breeding grounds, and even to the core areas of Baer's pochard's, which makes the hypothesis possible.
The research on its gut microbiota showed that the richest microorganism phyla of Baer's pochard are Bacillota, Pseudomonadota and Bacteroidota, which were consistent with those of the domestic goose, duck and chicken. The gut microbiota in diarrheic Baer's pochard is low in diversity, and the species were also significantly different from healthy individuals. Most species in reduced numbers are thought to be intestinal beneficial bacteria.
Threats and protection
Baer's pochard was once a common species in its range, but is now very rare. Mature individuals may be less than 1,000. According to records in China, there were 16,792 wintering individuals from 1986/87 to 1992/93, but only 3,472 from 1993/94 to 1998/99, and only 2,131 from 2002/03 to 2010/11. Bangladesh had more than 3,000 in 1996, India had more than 1,400 in 1995 and 1997, Myanmar had about 500-1,000 in the 1990s, and 596 were counted in 1998 in Thailand. While by 1999/00-2004/05, only 719 were counted in all wintering grounds except China, and only 48 individuals in 2005/06-2010/11. In China, hunting and habitat loss were considered to be the main threats. From 336 to 4,803 pochards were hunted annually in Honghu, Hubei from 1981 to 1997; in areas near Rudong County, maybe 3,000 are hunted every year. The wintering grounds have been significantly changed due to water pollution, fishing management, changes in aquatic plants, and the changing ecology of many wetlands in the Yangtze River floodplain. Factors in breeding and migrating grounds may also have contributed to its decline. The global decline shows no sign of slowing or stopping.
Baer's pochard was formerly classified as a vulnerable species by the IUCN. Recent research has shown that its numbers are decreasing more and more rapidly, and it was consequently uplisted to endangered status in 2008. In 2012, it was further uplisted to critically endangered. In 2014, the East Asian–Australasian Flyway Partnership (EAAFP) drafted the Baer's Pochard Task Force and it was endorsed in Jan 2015. Baer's pochard was listed as a first-class protected animal in China by 2021. In 2022, media reports state that the first captive population in China was established in the Beijing Zoo, with totally 54 individuals. It is planned to be further expanded and used for reintroduction.
A study published in 2022 showed that most breeding sites (81.8%) and suitable habitats (94%) are not located in protected areas, and overlap with large cities. Current protected areas may be less effective for the conservation under predicted global climate change, closely coordinated cross-border cooperation would be critical for Baer's pochard
This is just a finger stamp (dirty finger)
Canon 200D + inverted 18-55mm objective. 5 photos stacked using Zerena
Baer's pochard (Aythya baeri) is a diving duck found in eastern Asia. It is a resident bird in North and Central China, formerly bred in southeast Russia and Northeast China, migrating in winter to southern China, Vietnam, Japan, and India. Baer's pochard is a monotypic species. The holotype was collected in middle Amur.
It has a distinctive black head and neck with green gloss not present elsewhere in Aythya. While in poor light, it is likely to look completely black. It is very similar and closely related to the ferruginous duck, and they were previously considered to be a single species; Baer's pochard is differentiated by its white flanks when floating on the water, as well as its larger size and longer, more rounded head.
Its breeding season varies by latitude and environment. The nest, built from sedges, reeds and other plants, is placed among emergent vegetation, usually in shallow water or on small islands or ridges. Its clutch size ranges from 5 to 14. Males usually take on sentry duty, and females take on the responsibility of incubating.
Baer's pochard was once a common species in its range, but is now very rare. The number of mature individuals may be less than 1,000, and its population is still declining. Hunting and habitat loss are considered to be the main reasons. This species has been classified as critically endangered by the IUCN, and listed as a first-class protected animal in China.
Taxonomy
Baer's pochard was first scientifically described in 1863 as Anas baeri by Gustav Radde in his book Reisen im Süden von Ost-Sibirien. The epithet and English common name commemorate the Baltic German naturalist Karl Ernst von Baer. It is also called eastern white-eye, Siberian white-eye, Baer's white-eye and green-headed pochard. The holotype was collected from a small flock in middle Amur during the breeding season. In 1929, when British ornithologist E. C. Stuart Baker studied the birds of British India, he treated Baer's pochard and ferruginous duck as conspecific. However, Chinese ornithologist Tso-hsin Cheng treated them as two distinct species, as they had breeding grounds which did not overlap, and he had seen no evidence of hybridisation. While the species was long thought to have arisen from eastern populations of the ferruginous duck, American ornithologist Paul Johnsgard says its behaviors suggest it may instead be more closely related to the hardhead.
American ornithologist Bradley Curtis Livezey published a phylogenetic study based on morphological data in 1996, in which he proposed his view on the relationship among Tribe Aythyini. Baer's pochard, ferruginous duck, hardhead and Madagascar pochard are classified in subgenus Nyroca (the "white-eyes"), intrasubgenus relationship is unclear, but the ferruginous duck was suggested to be the sister group of Baer's pochard. The subgenus Aythya (the "scapu", including New Zealand Scaup, ring-necked duck, tufted duck, greater scaup and lesser scaup) is the sister group of subgenus Nyroca. The subgenus Aristonetta (the "redheads", including the common pochard, canvasback and redhead) is the sister group of all other pochards.
Two molecular phylogenetic studies on Anseriformes or Anatidae were published in 2000s, some mitochondrial genes were sequenced, but Baer's pochard was absent in both of them. The mitochondrial genome of Baer's pochard was sequenced and published in 2021. Molecular phylogenetic studies determined the relationships among Baer's pochard and other closely related species:
Tribe. Aythyini
Aythya
Baer's pochard Aythya baeri
Tufted Duck A. fuligula
Common pochard A. ferina
Redhead A. americana
Netta
Red-crested pochard Netta rufina
Asarcornis
White-winged duck Asarcornis scutulata
Description
The Baer's pochard is 41–47 cm (16–19 in) long with a 70–79 cm (28–31 in) wingspan. The male is slightly larger, weighing on average 500–730 g (18–26 oz), wings lengthed 18.6–20.3 cm (7.3–8.0 in), tail at 53–60 mm (2.1–2.4 in), and culmen at 38–44 mm (1.5–1.7 in). Relatively, the female weighing on average 590–655 g (20.8–23.1 oz), wings lengthed 19.1–20.5 cm (7.5–8.1 in), tail at 51–64 mm (2.0–2.5 in), and culmen at 40–44 mm (1.6–1.7 in). Both male and female's tarsometatarsus lengthed 33–34.7 mm (1.30–1.37 in).
Breeding male has a black head and neck with green gloss, white or paler yellow eyes, blackish-brown back, dark chestnut breast, white or light chestnut flanks and a short and low tail. The green gloss on its head is unique among Aythya. While it is likely to look completely black in poor light. Female has a dark brown head and neck that blend into the chestnut-brown breast and flanks. Eclipse and first-winter male resembles female, but retain the white eyes, while female has brown eyes. Both male and female have wide white speculum feathers, white vent-side, dark-grey bill, black nail and dark-grey tarsometatarsus.
It is similar to its close relative, the ferruginous duck (A. nyroca), both have white vent-side and iris in males, black nail, and wide white speculum feathers. Although Baer's pochard is bigger, has a longer head, body and bill. Unlike the ferruginous duck's tall and triangular head, Baer's pochard has a more rounded head and a flatter forehead. The white part on the belly extends to its flanks in Baer's pochard, which is visible when floating on the water, while the ferruginous duck has a smaller white part on its belly. The female Baer's pochard has a distinctly bright chestnut spot at the lore, which is absent in ferruginous duck.
Baer's pochard is usually a quieter duck, but during its courtship display, both sexes give harsh graaaak. Females may give kura kura kura and males may give kuro kuro at other times.
Distribution
Baer's pochard traditionally bred in the Amur and Ussuri basins in Northeast China and the southeastern Russian Far East. In recent years, it has also colonised North China and Central China. It winters in most areas south of the Yellow River in China, Taiwan, Japan, Bangladesh, India, North Korea, Laos, Myanmar, Nepal, Thailand and Vietnam, and occasionally appears in Bhutan, South Korea, Philippines or Pakistan as a rare vagrant. It leaves its wintering grounds by mid-March and returns to them by mid-October or early November.
The species has become extremely rare in its traditional breeding areas, and since 2010, there have been no confirmed breeding reports in all sites north of Beijing. However, the numbers recorded during the breeding season are smaller than those recorded in winter, so there may still be unknown breeding sites. For example, there are some doubtful breeding reports in the Chinese part of Lake Khanka, the Russian part of Lake Khasan, and the Muraviovka Park [ru]. Since 2012, new breeding sites have been discovered in several provinces of China, including Hebei, Hubei and Jiangxi; the latter two cities are far from traditional breeding sites in the Amur and Ussuri basins.[1] In these new breeding areas, warmer climate conditions provide a longer breeding season (about twice as long as in the Amur and Ussuri basins) which allows birds to lay a replacement clutch if their first clutch fails. Baer's pochard is no longer migratory in central and eastern China.
The wintering grounds have also contracted significantly in recent years. Since at least the winter of 2010-2011, Baer's pochard no longer winters in any site outside mainland China, except as a vagrant. In its wintering grounds in mainland China, the population has also declined severely, by more than 99%.
Behaviour and ecology
Baer's pochard is a shy species, that inhabit open, slow-flowing lakes, swamps and ponds. It breeds around lakes with rich aquatic vegetation, nesting in dense grass, flooded tussock meadows, or flooded shrubby meadows. In winter, it forms large flocks on large and open freshwater lakes and reservoirs with other pochards. It has strong wings, and can flyor walk at high speeds. It is also good at diving and swimming, and can quickly take off from the water when threatened or disturbed. In migrating season, they form small groups of more than 10 or dozens of birds, flying at low altitudes in wedge-shaped formations. During winter, Baer's pochard sleeps during the day, leaves for unknown feeding sites with other ducks in the dusk, and returns before dawn. Little is known about their diet beyond aquatic plants, grass seeds and molluscs.
Breeding
Baer's pochard appears to have a monogamous mating system, at least within a breeding season. In traditional breeding grounds in northeastern China, Baer's pochard gathers in gaps in the ice before it completely thawed. After the ice season, it gathers on the large, open lakes. They breed from mid-to-late May. While in Fuhe Wetland in Wuhan, Hubei, Baer's pochard gathers in large groups on the open lakes before breeding season. It is divided into small groups in mid-April, in which they will courting and mating. During courtship, the male swims around the female, repeatedly nods his head up and down. When other males approach, it swims toward them quickly to drive them away, but there is no violent fight between them. The female also nods her head in response. When the male approaches, the female straightens her neck and lowers her head to the water. He then climbs onto her body and bites her nape feathers to mate. After the mating, the male and female leave the flock for nesting.
Baer's pochard's nest is circular cylindrical, located among emergent vegetation, usually in shallow water or on small islands or ridges. The nest is made of sedges, reeds and other plants collected from the immediate vicinity, lined with a layer of down. Its clutch ranged from 5 to 14, with an average of 9.7. Males usually take on sentry duty at about 10 meters from the nest during hatching. Females leave the nest to forage 2–3 times a day, usually during 6:00-20:00, and lasted for 27–240 min. They cover the eggs with nest materials during forging, and place them onto their back when coming back. If water levels are elevated by heavy rainfall or human activity, females increase the height of the nest to avoid flooding. During the hottest days, females often stand on the nest and shelter eggs from the strong sunlight, whilst allowing circulation of air around them. Females also take water into their plumage and use it to cool the eggs. The incubation lasted for 23-26 days.
Studies have shown that the nest survival rate[note 3] of Baer's pochards is about 14–45%, and each clutch may lose one to nine eggs. About 20-30% of eggs hatched successfully, and 3–16 young fledged per nest. There are three major reasons contributing to the failure, including nest desertion (abandoned by parents), nest predation (mainly by Siberian Weasels) and flooding. The proportion of these causes varies among years. In addition, most of the breeding sites in Wuhan are Crayfish farms, the farming work and eggs collection may also be hindrances.
Biological interaction
Incomplete inter- and intra-specific brood parasitism were found in Baer's pochard. In Xianghai National Nature Reserve [zh], Baer's pochards could parasitize gadwall and common pochard, and may be parasitized by common pochard. In Wuhan, Baer's pochard shares breeding sites with cotton teal, eastern spot-billed duck and mallard. Interspecific brood parasitism was not observed. Intraspecific parasitic was found in Wuhan. If caught, the parasite will get attacked by the host.
Baer's pochard has hybridized with lesser scaup, common pochard, ferruginous duck, New Zealand scaup, chestnut teal and wood duck in captivity. Ferruginous duck was observed displaying to Baer's pochards several times in China and South Korea. Some individuals showed mixed characteristics of common, ferruginous and Baer's pochards, so they may be currently hybridising in the wild. The Baer's pochard has declined sharply in recent years, but the ferruginous and common pochard has expanded their breeding grounds, and even to the core areas of Baer's pochard's, which makes the hypothesis possible.
The research on its gut microbiota showed that the richest microorganism phyla of Baer's pochard are Bacillota, Pseudomonadota and Bacteroidota, which were consistent with those of the domestic goose, duck and chicken. The gut microbiota in diarrheic Baer's pochard is low in diversity, and the species were also significantly different from healthy individuals. Most species in reduced numbers are thought to be intestinal beneficial bacteria.
Threats and protection
Baer's pochard was once a common species in its range, but is now very rare. Mature individuals may be less than 1,000. According to records in China, there were 16,792 wintering individuals from 1986/87 to 1992/93, but only 3,472 from 1993/94 to 1998/99, and only 2,131 from 2002/03 to 2010/11. Bangladesh had more than 3,000 in 1996, India had more than 1,400 in 1995 and 1997, Myanmar had about 500-1,000 in the 1990s, and 596 were counted in 1998 in Thailand. While by 1999/00-2004/05, only 719 were counted in all wintering grounds except China, and only 48 individuals in 2005/06-2010/11. In China, hunting and habitat loss were considered to be the main threats. From 336 to 4,803 pochards were hunted annually in Honghu, Hubei from 1981 to 1997; in areas near Rudong County, maybe 3,000 are hunted every year. The wintering grounds have been significantly changed due to water pollution, fishing management, changes in aquatic plants, and the changing ecology of many wetlands in the Yangtze River floodplain. Factors in breeding and migrating grounds may also have contributed to its decline. The global decline shows no sign of slowing or stopping.
Baer's pochard was formerly classified as a vulnerable species by the IUCN. Recent research has shown that its numbers are decreasing more and more rapidly, and it was consequently uplisted to endangered status in 2008. In 2012, it was further uplisted to critically endangered. In 2014, the East Asian–Australasian Flyway Partnership (EAAFP) drafted the Baer's Pochard Task Force and it was endorsed in Jan 2015. Baer's pochard was listed as a first-class protected animal in China by 2021. In 2022, media reports state that the first captive population in China was established in the Beijing Zoo, with totally 54 individuals. It is planned to be further expanded and used for reintroduction.
A study published in 2022 showed that most breeding sites (81.8%) and suitable habitats (94%) are not located in protected areas, and overlap with large cities. Current protected areas may be less effective for the conservation under predicted global climate change, closely coordinated cross-border cooperation would be critical for Baer's pochard
Baer's pochard (Aythya baeri) is a diving duck found in eastern Asia. It is a resident bird in North and Central China, formerly bred in southeast Russia and Northeast China, migrating in winter to southern China, Vietnam, Japan, and India. Baer's pochard is a monotypic species. The holotype was collected in middle Amur.
It has a distinctive black head and neck with green gloss not present elsewhere in Aythya. While in poor light, it is likely to look completely black. It is very similar and closely related to the ferruginous duck, and they were previously considered to be a single species; Baer's pochard is differentiated by its white flanks when floating on the water, as well as its larger size and longer, more rounded head.
Its breeding season varies by latitude and environment. The nest, built from sedges, reeds and other plants, is placed among emergent vegetation, usually in shallow water or on small islands or ridges. Its clutch size ranges from 5 to 14. Males usually take on sentry duty, and females take on the responsibility of incubating.
Baer's pochard was once a common species in its range, but is now very rare. The number of mature individuals may be less than 1,000, and its population is still declining. Hunting and habitat loss are considered to be the main reasons. This species has been classified as critically endangered by the IUCN, and listed as a first-class protected animal in China.
Taxonomy
Baer's pochard was first scientifically described in 1863 as Anas baeri by Gustav Radde in his book Reisen im Süden von Ost-Sibirien. The epithet and English common name commemorate the Baltic German naturalist Karl Ernst von Baer. It is also called eastern white-eye, Siberian white-eye, Baer's white-eye and green-headed pochard. The holotype was collected from a small flock in middle Amur during the breeding season. In 1929, when British ornithologist E. C. Stuart Baker studied the birds of British India, he treated Baer's pochard and ferruginous duck as conspecific. However, Chinese ornithologist Tso-hsin Cheng treated them as two distinct species, as they had breeding grounds which did not overlap, and he had seen no evidence of hybridisation. While the species was long thought to have arisen from eastern populations of the ferruginous duck, American ornithologist Paul Johnsgard says its behaviors suggest it may instead be more closely related to the hardhead.
American ornithologist Bradley Curtis Livezey published a phylogenetic study based on morphological data in 1996, in which he proposed his view on the relationship among Tribe Aythyini. Baer's pochard, ferruginous duck, hardhead and Madagascar pochard are classified in subgenus Nyroca (the "white-eyes"), intrasubgenus relationship is unclear, but the ferruginous duck was suggested to be the sister group of Baer's pochard. The subgenus Aythya (the "scapu", including New Zealand Scaup, ring-necked duck, tufted duck, greater scaup and lesser scaup) is the sister group of subgenus Nyroca. The subgenus Aristonetta (the "redheads", including the common pochard, canvasback and redhead) is the sister group of all other pochards.
Two molecular phylogenetic studies on Anseriformes or Anatidae were published in 2000s, some mitochondrial genes were sequenced, but Baer's pochard was absent in both of them. The mitochondrial genome of Baer's pochard was sequenced and published in 2021. Molecular phylogenetic studies determined the relationships among Baer's pochard and other closely related species:
Tribe. Aythyini
Aythya
Baer's pochard Aythya baeri
Tufted Duck A. fuligula
Common pochard A. ferina
Redhead A. americana
Netta
Red-crested pochard Netta rufina
Asarcornis
White-winged duck Asarcornis scutulata
Description
The Baer's pochard is 41–47 cm (16–19 in) long with a 70–79 cm (28–31 in) wingspan. The male is slightly larger, weighing on average 500–730 g (18–26 oz), wings lengthed 18.6–20.3 cm (7.3–8.0 in), tail at 53–60 mm (2.1–2.4 in), and culmen at 38–44 mm (1.5–1.7 in). Relatively, the female weighing on average 590–655 g (20.8–23.1 oz), wings lengthed 19.1–20.5 cm (7.5–8.1 in), tail at 51–64 mm (2.0–2.5 in), and culmen at 40–44 mm (1.6–1.7 in). Both male and female's tarsometatarsus lengthed 33–34.7 mm (1.30–1.37 in).
Breeding male has a black head and neck with green gloss, white or paler yellow eyes, blackish-brown back, dark chestnut breast, white or light chestnut flanks and a short and low tail. The green gloss on its head is unique among Aythya. While it is likely to look completely black in poor light. Female has a dark brown head and neck that blend into the chestnut-brown breast and flanks. Eclipse and first-winter male resembles female, but retain the white eyes, while female has brown eyes. Both male and female have wide white speculum feathers, white vent-side, dark-grey bill, black nail and dark-grey tarsometatarsus.
It is similar to its close relative, the ferruginous duck (A. nyroca), both have white vent-side and iris in males, black nail, and wide white speculum feathers. Although Baer's pochard is bigger, has a longer head, body and bill. Unlike the ferruginous duck's tall and triangular head, Baer's pochard has a more rounded head and a flatter forehead. The white part on the belly extends to its flanks in Baer's pochard, which is visible when floating on the water, while the ferruginous duck has a smaller white part on its belly. The female Baer's pochard has a distinctly bright chestnut spot at the lore, which is absent in ferruginous duck.
Baer's pochard is usually a quieter duck, but during its courtship display, both sexes give harsh graaaak. Females may give kura kura kura and males may give kuro kuro at other times.
Distribution
Baer's pochard traditionally bred in the Amur and Ussuri basins in Northeast China and the southeastern Russian Far East. In recent years, it has also colonised North China and Central China. It winters in most areas south of the Yellow River in China, Taiwan, Japan, Bangladesh, India, North Korea, Laos, Myanmar, Nepal, Thailand and Vietnam, and occasionally appears in Bhutan, South Korea, Philippines or Pakistan as a rare vagrant. It leaves its wintering grounds by mid-March and returns to them by mid-October or early November.
The species has become extremely rare in its traditional breeding areas, and since 2010, there have been no confirmed breeding reports in all sites north of Beijing. However, the numbers recorded during the breeding season are smaller than those recorded in winter, so there may still be unknown breeding sites. For example, there are some doubtful breeding reports in the Chinese part of Lake Khanka, the Russian part of Lake Khasan, and the Muraviovka Park [ru]. Since 2012, new breeding sites have been discovered in several provinces of China, including Hebei, Hubei and Jiangxi; the latter two cities are far from traditional breeding sites in the Amur and Ussuri basins.[1] In these new breeding areas, warmer climate conditions provide a longer breeding season (about twice as long as in the Amur and Ussuri basins) which allows birds to lay a replacement clutch if their first clutch fails. Baer's pochard is no longer migratory in central and eastern China.
The wintering grounds have also contracted significantly in recent years. Since at least the winter of 2010-2011, Baer's pochard no longer winters in any site outside mainland China, except as a vagrant. In its wintering grounds in mainland China, the population has also declined severely, by more than 99%.
Behaviour and ecology
Baer's pochard is a shy species, that inhabit open, slow-flowing lakes, swamps and ponds. It breeds around lakes with rich aquatic vegetation, nesting in dense grass, flooded tussock meadows, or flooded shrubby meadows. In winter, it forms large flocks on large and open freshwater lakes and reservoirs with other pochards. It has strong wings, and can flyor walk at high speeds. It is also good at diving and swimming, and can quickly take off from the water when threatened or disturbed. In migrating season, they form small groups of more than 10 or dozens of birds, flying at low altitudes in wedge-shaped formations. During winter, Baer's pochard sleeps during the day, leaves for unknown feeding sites with other ducks in the dusk, and returns before dawn. Little is known about their diet beyond aquatic plants, grass seeds and molluscs.
Breeding
Baer's pochard appears to have a monogamous mating system, at least within a breeding season. In traditional breeding grounds in northeastern China, Baer's pochard gathers in gaps in the ice before it completely thawed. After the ice season, it gathers on the large, open lakes. They breed from mid-to-late May. While in Fuhe Wetland in Wuhan, Hubei, Baer's pochard gathers in large groups on the open lakes before breeding season. It is divided into small groups in mid-April, in which they will courting and mating. During courtship, the male swims around the female, repeatedly nods his head up and down. When other males approach, it swims toward them quickly to drive them away, but there is no violent fight between them. The female also nods her head in response. When the male approaches, the female straightens her neck and lowers her head to the water. He then climbs onto her body and bites her nape feathers to mate. After the mating, the male and female leave the flock for nesting.
Baer's pochard's nest is circular cylindrical, located among emergent vegetation, usually in shallow water or on small islands or ridges. The nest is made of sedges, reeds and other plants collected from the immediate vicinity, lined with a layer of down. Its clutch ranged from 5 to 14, with an average of 9.7. Males usually take on sentry duty at about 10 meters from the nest during hatching. Females leave the nest to forage 2–3 times a day, usually during 6:00-20:00, and lasted for 27–240 min. They cover the eggs with nest materials during forging, and place them onto their back when coming back. If water levels are elevated by heavy rainfall or human activity, females increase the height of the nest to avoid flooding. During the hottest days, females often stand on the nest and shelter eggs from the strong sunlight, whilst allowing circulation of air around them. Females also take water into their plumage and use it to cool the eggs. The incubation lasted for 23-26 days.
Studies have shown that the nest survival rate[note 3] of Baer's pochards is about 14–45%, and each clutch may lose one to nine eggs. About 20-30% of eggs hatched successfully, and 3–16 young fledged per nest. There are three major reasons contributing to the failure, including nest desertion (abandoned by parents), nest predation (mainly by Siberian Weasels) and flooding. The proportion of these causes varies among years. In addition, most of the breeding sites in Wuhan are Crayfish farms, the farming work and eggs collection may also be hindrances.
Biological interaction
Incomplete inter- and intra-specific brood parasitism were found in Baer's pochard. In Xianghai National Nature Reserve [zh], Baer's pochards could parasitize gadwall and common pochard, and may be parasitized by common pochard. In Wuhan, Baer's pochard shares breeding sites with cotton teal, eastern spot-billed duck and mallard. Interspecific brood parasitism was not observed. Intraspecific parasitic was found in Wuhan. If caught, the parasite will get attacked by the host.
Baer's pochard has hybridized with lesser scaup, common pochard, ferruginous duck, New Zealand scaup, chestnut teal and wood duck in captivity. Ferruginous duck was observed displaying to Baer's pochards several times in China and South Korea. Some individuals showed mixed characteristics of common, ferruginous and Baer's pochards, so they may be currently hybridising in the wild. The Baer's pochard has declined sharply in recent years, but the ferruginous and common pochard has expanded their breeding grounds, and even to the core areas of Baer's pochard's, which makes the hypothesis possible.
The research on its gut microbiota showed that the richest microorganism phyla of Baer's pochard are Bacillota, Pseudomonadota and Bacteroidota, which were consistent with those of the domestic goose, duck and chicken. The gut microbiota in diarrheic Baer's pochard is low in diversity, and the species were also significantly different from healthy individuals. Most species in reduced numbers are thought to be intestinal beneficial bacteria.
Threats and protection
Baer's pochard was once a common species in its range, but is now very rare. Mature individuals may be less than 1,000. According to records in China, there were 16,792 wintering individuals from 1986/87 to 1992/93, but only 3,472 from 1993/94 to 1998/99, and only 2,131 from 2002/03 to 2010/11. Bangladesh had more than 3,000 in 1996, India had more than 1,400 in 1995 and 1997, Myanmar had about 500-1,000 in the 1990s, and 596 were counted in 1998 in Thailand. While by 1999/00-2004/05, only 719 were counted in all wintering grounds except China, and only 48 individuals in 2005/06-2010/11. In China, hunting and habitat loss were considered to be the main threats. From 336 to 4,803 pochards were hunted annually in Honghu, Hubei from 1981 to 1997; in areas near Rudong County, maybe 3,000 are hunted every year. The wintering grounds have been significantly changed due to water pollution, fishing management, changes in aquatic plants, and the changing ecology of many wetlands in the Yangtze River floodplain. Factors in breeding and migrating grounds may also have contributed to its decline. The global decline shows no sign of slowing or stopping.
Baer's pochard was formerly classified as a vulnerable species by the IUCN. Recent research has shown that its numbers are decreasing more and more rapidly, and it was consequently uplisted to endangered status in 2008. In 2012, it was further uplisted to critically endangered. In 2014, the East Asian–Australasian Flyway Partnership (EAAFP) drafted the Baer's Pochard Task Force and it was endorsed in Jan 2015. Baer's pochard was listed as a first-class protected animal in China by 2021. In 2022, media reports state that the first captive population in China was established in the Beijing Zoo, with totally 54 individuals. It is planned to be further expanded and used for reintroduction.
A study published in 2022 showed that most breeding sites (81.8%) and suitable habitats (94%) are not located in protected areas, and overlap with large cities. Current protected areas may be less effective for the conservation under predicted global climate change, closely coordinated cross-border cooperation would be critical for Baer's pochard
Bees are flying insects closely related to wasps and ants, known for their role in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyletic lineage within the superfamily Apoidea. They are presently considered a clade, called Anthophila. There are over 16,000 known species of bees in seven recognized biological families. Some species – including honey bees, bumblebees, and stingless bees – live socially in colonies while some species – including mason bees, carpenter bees, leafcutter bees, and sweat bees – are solitary.
Bees are found on every continent except for Antarctica, in every habitat on the planet that contains insect-pollinated flowering plants. The most common bees in the Northern Hemisphere are the Halictidae, or sweat bees, but they are small and often mistaken for wasps or flies. Bees range in size from tiny stingless bee species, whose workers are less than 2 millimetres long, to Megachile pluto, the largest species of leafcutter bee, whose females can attain a length of 39 millimetres.
Bees feed on nectar and pollen, the former primarily as an energy source and the latter primarily for protein and other nutrients. Most pollen is used as food for their larvae. Vertebrate predators of bees include birds such as bee-eaters; insect predators include beewolves and dragonflies.
Bee pollination is important both ecologically and commercially, and the decline in wild bees has increased the value of pollination by commercially managed hives of honey bees. The analysis of 353 wild bee and hoverfly species across Britain from 1980 to 2013 found the insects have been lost from a quarter of the places they inhabited in 1980.
Human beekeeping or apiculture has been practised for millennia, since at least the times of Ancient Egypt and Ancient Greece. Bees have appeared in mythology and folklore, through all phases of art and literature from ancient times to the present day, although primarily focused in the Northern Hemisphere where beekeeping is far more common.
EVOLUTION
The ancestors of bees were wasps in the family Crabronidae, which were predators of other insects. The switch from insect prey to pollen may have resulted from the consumption of prey insects which were flower visitors and were partially covered with pollen when they were fed to the wasp larvae. This same evolutionary scenario may have occurred within the vespoid wasps, where the pollen wasps evolved from predatory ancestors. Until recently, the oldest non-compression bee fossil had been found in New Jersey amber, Cretotrigona prisca of Cretaceous age, a corbiculate bee. A bee fossil from the early Cretaceous (~100 mya), Melittosphex burmensis, is considered "an extinct lineage of pollen-collecting Apoidea sister to the modern bees". Derived features of its morphology (apomorphies) place it clearly within the bees, but it retains two unmodified ancestral traits (plesiomorphies) of the legs (two mid-tibial spurs, and a slender hind basitarsus), showing its transitional status. By the Eocene (~45 mya) there was already considerable diversity among eusocial bee lineages.
The highly eusocial corbiculate Apidae appeared roughly 87 Mya, and the Allodapini (within the Apidae) around 53 Mya. The Colletidae appear as fossils only from the late Oligocene (~25 Mya) to early Miocene. The Melittidae are known from Palaeomacropis eocenicus in the Early Eocene. The Megachilidae are known from trace fossils (characteristic leaf cuttings) from the Middle Eocene. The Andrenidae are known from the Eocene-Oligocene boundary, around 34 Mya, of the Florissant shale. The Halictidae first appear in the Early Eocene with species found in amber. The Stenotritidae are known from fossil brood cells of Pleistocene age.
COEVOLUTION
The earliest animal-pollinated flowers were shallow, cup-shaped blooms pollinated by insects such as beetles, so the syndrome of insect pollination was well established before the first appearance of bees. The novelty is that bees are specialized as pollination agents, with behavioral and physical modifications that specifically enhance pollination, and are the most efficient pollinating insects. In a process of coevolution, flowers developed floral rewards such as nectar and longer tubes, and bees developed longer tongues to extract the nectar. Bees also developed structures known as scopal hairs and pollen baskets to collect and carry pollen. The location and type differ among and between groups of bees. Most species have scopal hairs on their hind legs or on the underside of their abdomens. Some species in the family Apidae have pollen baskets on their hind legs, while very few lack these and instead collect pollen in their crops. The appearance of these structures drove the adaptive radiation of the angiosperms, and, in turn, bees themselves. Bees coevolved not only with flowers but it is believed that some species coevolved with mites. Some provide tufts of hairs called acarinaria that appear to provide lodgings for mites; in return, it is believed that mites eat fungi that attack pollen, so the relationship in this case may be mutualistc.
CHARACTERISTICS
Bees differ from closely related groups such as wasps by having branched or plume-like setae (hairs), combs on the forelimbs for cleaning their antennae, small anatomical differences in limb structure, and the venation of the hind wings; and in females, by having the seventh dorsal abdominal plate divided into two half-plates.
Bees have the following characteristics:
A pair of large compound eyes which cover much of the surface of the head. Between and above these are three small simple eyes (ocelli) which provide information on light intensity.
The antennae usually have 13 segments in males and 12 in females, and are geniculate, having an elbow joint part way along. They house large numbers of sense organs that can detect touch (mechanoreceptors), smell and taste; and small, hairlike mechanoreceptors that can detect air movement so as to "hear" sounds.
The mouthparts are adapted for both chewing and sucking by having both a pair of mandibles and a long proboscis for sucking up nectar.
The thorax has three segments, each with a pair of robust legs, and a pair of membranous wings on the hind two segments. The front legs of corbiculate bees bear combs for cleaning the antennae, and in many species the hind legs bear pollen baskets, flattened sections with incurving hairs to secure the collected pollen. The wings are synchronised in flight, and the somewhat smaller hind wings connect to the forewings by a row of hooks along their margin which connect to a groove in the forewing.
The abdomen has nine segments, the hindermost three being modified into the sting.
The largest species of bee is thought to be Wallace's giant bee Megachile pluto, whose females can attain a length of 39 millimetres. The smallest species may be dwarf stingless bees in the tribe Meliponini whose workers are less than 2 millimetres in length.
SOCIALITY
HAPLODIPLOID BREEDING SYSTEM
According to inclusive fitness theory, organisms can gain fitness not just through increasing their own reproductive output, but also that of close relatives. In evolutionary terms, individuals should help relatives when Cost < Relatedness * Benefit. The requirements for eusociality are more easily fulfilled by haplodiploid species such as bees because of their unusual relatedness structure.
In haplodiploid species, females develop from fertilized eggs and males from unfertilized eggs. Because a male is haploid (has only one copy of each gene), his daughters (which are diploid, with two copies of each gene) share 100% of his genes and 50% of their mother's. Therefore, they share 75% of their genes with each other. This mechanism of sex determination gives rise to what W. D. Hamilton termed "supersisters", more closely related to their sisters than they would be to their own offspring. Workers often do not reproduce, but they can pass on more of their genes by helping to raise their sisters (as queens) than they would by having their own offspring (each of which would only have 50% of their genes), assuming they would produce similar numbers. This unusual situation has been proposed as an explanation of the multiple (at least 9) evolutions of eusociality within Hymenoptera.
Haplodiploidy is neither necessary nor sufficient for eusociality. Some eusocial species such as termites are not haplodiploid. Conversely, all bees are haplodiploid but not all are eusocial, and among eusocial species many queens mate with multiple males, creating half-sisters that share only 25% of each-other's genes. But, monogamy (queens mating singly) is the ancestral state for all eusocial species so far investigated, so it is likely that haplodiploidy contributed to the evolution of eusociality in bees.
EUSOCIALIT
Bees may be solitary or may live in various types of communities. Eusociality appears to have originated from at least three independent origins in halictid bees. The most advanced of these are species with eusocial colonies; these are characterised by cooperative brood care and a division of labour into reproductive and non-reproductive adults, plus overlapping generations. This division of labour creates specialized groups within eusocial societies which are called castes. In some species, groups of cohabiting females may be sisters, and if there is a division of labour within the group, they are considered semisocial. The group is called eusocial if, in addition, the group consists of a mother (the queen) and her daughters (workers). When the castes are purely behavioural alternatives, with no morphological differentiation other than size, the system is considered primitively eusocial, as in many paper wasps; when the castes are morphologically discrete, the system is considered highly eusocial.True honey bees (genus Apis, of which seven species are currently recognized) are highly eusocial, and are among the best known insects. Their colonies are established by swarms, consisting of a queen and several hundred workers. There are 29 subspecies of one of these species, Apis mellifera, native to Europe, the Middle East, and Africa. Africanized bees are a hybrid strain of A. mellifera that escaped from experiments involving crossing European and African subspecies; they are extremely defensive.[Stingless bees are also highly eusocial. They practise mass provisioning, with complex nest architecture and perennial colonies also established via swarming.
Many bumblebees are eusocial, similar to the eusocial Vespidae such as hornets in that the queen initiates a nest on her own rather than by swarming. Bumblebee colonies typically have from 50 to 200 bees at peak population, which occurs in mid to late summer. Nest architecture is simple, limited by the size of the pre-existing nest cavity, and colonies rarely last more than a year. In 2011, the International Union for Conservation of Nature set up the Bumblebee Specialist Group to review the threat status of all bumblebee species worldwide using the IUCN Red List criteria.
There are many more species of primitively eusocial than highly eusocial bees, but they have been studied less often. Most are in the family Halictidae, or "sweat bees". Colonies are typically small, with a dozen or fewer workers, on average. Queens and workers differ only in size, if at all. Most species have a single season colony cycle, even in the tropics, and only mated females hibernate. A few species have long active seasons and attain colony sizes in the hundreds, such as Halictus hesperus. Some species are eusocial in parts of their range and solitary in others, or have a mix of eusocial and solitary nests in the same population. The orchid bees (Apidae) include some primitively eusocial species with similar biology. Some allodapine bees (Apidae) form primitively eusocial colonies, with progressive provisioning: a larva's food is supplied gradually as it develops, as is the case in honey bees and some bumblebees.
SOLITARY AND COMMUNAL BEES
Most other bees, including familiar insects such as carpenter bees, leafcutter bees and mason bees are solitary in the sense that every female is fertile, and typically inhabits a nest she constructs herself. There is no division of labor so these nests lack queens and worker bees for these species. Solitary bees typically produce neither honey nor beeswax. Bees collect pollen to feed their young, and have the necessary adaptations to do this. However, certain wasp species such as pollen wasps have similar behaviours, and a few species of bee scavenge from carcases to feed their offspring. Solitary bees are important pollinators; they gather pollen to provision their nests with food for their brood. Often it is mixed with nectar to form a paste-like consistency. Some solitary bees have advanced types of pollen-carrying structures on their bodies. Very few species of solitary bee are being cultured for commercial pollination. Most of these species belong to a distinct set of genera which are commonly known by their nesting behavior or preferences, namely: carpenter bees, sweat bees, mason bees, plasterer bees, squash bees, dwarf carpenter bees, leafcutter bees, alkali bees and digger bees.Most solitary bees nest in the ground in a variety of soil textures and conditions while others create nests in hollow reeds or twigs, holes in wood. The female typically creates a compartment (a "cell") with an egg and some provisions for the resulting larva, then seals it off. A nest may consist of numerous cells. When the nest is in wood, usually the last (those closer to the entrance) contain eggs that will become males. The adult does not provide care for the brood once the egg is laid, and usually dies after making one or more nests. The males typically emerge first and are ready for mating when the females emerge. Solitary bees are either stingless or very unlikely to sting (only in self-defense, if ever). While solitary, females each make individual nests. Some species, such as the European mason bee Hoplitis anthocopoides, and the Dawson's Burrowing bee, Amegilla dawsoni, are gregarious, preferring to make nests near others of the same species, and giving the appearance of being social. Large groups of solitary bee nests are called aggregations, to distinguish them from colonies. In some species, multiple females share a common nest, but each makes and provisions her own cells independently. This type of group is called "communal" and is not uncommon. The primary advantage appears to be that a nest entrance is easier to defend from predators and parasites when multiple females use that same entrance regularly
BIOLOGY
LIFE CYCLE
The life cycle of a bee, be it a solitary or social species, involves the laying of an egg, the development through several moults of a legless larva, a pupation stage during which the insect undergoes complete metamorphosis, followed by the emergence of a winged adult. Most solitary bees and bumble bees in temperate climates overwinter as adults or pupae and emerge in spring when increasing numbers of flowering plants come into bloom. The males usually emerge first and search for females with which to mate. The sex of a bee is determined by whether or not the egg is fertilised; after mating, a female stores the sperm, and determines which sex is required at the time each individual egg is laid, fertilised eggs producing female offspring and unfertilised eggs, males. Tropical bees may have several generations in a year and no diapause stage.
The egg is generally oblong, slightly curved and tapering at one end. Solitary bees, lay each egg in a separate cell with a supply of mixed pollen and nectar next to it. This may be rolled into a pellet or placed in a pile and is known as mass provisioning. Social bee species provision progressively, that is, they feed the larva regularly while it grows. The nest varies from a hole in the ground or in wood, in solitary bees, to a substantial structure with wax combs in bumblebees and honey bees.
In most species, larvae are whitish grubs, roughly oval and bluntly-pointed at both ends. They have 15 segments and spiracles in each segment for breathing. They have no legs but move within the cell, helped by tubercles on their sides. They have short horns on the head, jaws for chewing food and an appendage on either side of the mouth tipped with a bristle. There is a gland under the mouth that secretes a viscous liquid which solidifies into the silk they use to produce a cocoon. The cocoon is semi-transparent and the pupa can be seen through it. Over the course of a few days, the larva undergoes metamorphosis into a winged adult. When ready to emerge, the adult splits its skin dorsally and climbs out of the exuviae and breaks out of the cell.
FLIGHT
Antoine Magnan's 1934 book Le vol des insectes, says that he and André Sainte-Laguë had applied the equations of air resistance to insects and found that their flight could not be explained by fixed-wing calculations, but that "One shouldn't be surprised that the results of the calculations don't square with reality". This has led to a common misconception that bees "violate aerodynamic theory". In fact it merely confirms that bees do not engage in fixed-wing flight, and that their flight is explained by other mechanics, such as those used by helicopters. In 1996 it was shown that vortices created by many insects' wings helped to provide lift. High-speed cinematography and robotic mock-up of a bee wing showed that lift was generated by "the unconventional combination of short, choppy wing strokes, a rapid rotation of the wing as it flops over and reverses direction, and a very fast wing-beat frequency". Wing-beat frequency normally increases as size decreases, but as the bee's wing beat covers such a small arc, it flaps approximately 230 times per second, faster than a fruitfly (200 times per second) which is 80 times smaller.
NAVIGATION, COMMUNICATION AND FINDING FOOD
The ethologist Karl von Frisch studied navigation in the honey bee. He showed that honey bees communicate by the waggle dance, in which a worker indicates the location of a food source to other workers in the hive. He demonstrated that bees can recognize a desired compass direction in three different ways: by the sun, by the polarization pattern of the blue sky, and by the earth's magnetic field. He showed that the sun is the preferred or main compass; the other mechanisms are used under cloudy skies or inside a dark beehive. Bees navigate using spatial memory with a "rich, map-like organization".
DIGESTION
The gut of bees is relatively simple, but multiple metabolic strategies exist in the gut microbiota. Pollinating bees consume nectar and pollen, which require different digestion strategies by somewhat specialized bacteria. While nectar is a liquid of mostly monosaccharide sugars and so easily absorbed, pollen contains complex polysaccharides: branching pectin and hemicellulose. Approximately five groups of bacteria are involved in digestion. Three groups specialize in simple sugars (Snodgrassella and two groups of Lactobacillus), and two other groups in complex sugars (Gilliamella and Bifidobacterium). Digestion of pectin and hemicellulose is dominated by bacterial clades Gilliamella and Bifidobacterium respectively. Bacteria that cannot digest polysaccharides obtain enzymes from their neighbors, and bacteria that lack certain amino acids do the same, creating multiple ecological niches.
Although most bee species are nectarivorous and palynivorous, some are not. Particularly unusual are vulture bees in the genus Trigona, which consume carrion and wasp brood, turning meat into a honey-like substance.
ECOLOGY
FLORAL RELATIONSHIPS
Most bees are polylectic (generalist) meaning they collect pollen from a range of flowering plants, but some are oligoleges (specialists), in that they only gather pollen from one or a few species or genera of closely related plants. Specialist pollinators also include bee species which gather floral oils instead of pollen, and male orchid bees, which gather aromatic compounds from orchids (one of the few cases where male bees are effective pollinators). Bees are able to sense the presence of desirable flowers through ultraviolet patterning on flowers, floral odors, and even electromagnetic fields. Once landed, a bee then uses nectar quality and pollen taste to determine whether to continue visiting similar flowers.
In rare cases, a plant species may only be effectively pollinated by a single bee species, and some plants are endangered at least in part because their pollinator is also threatened. But, there is a pronounced tendency for oligolectic bees to be associated with common, widespread plants visited by multiple pollinator species. For example, the creosote bush in the arid parts of the United States southwest is associated with some 40 oligoleges.
AS MIMICS AND MODELS
Many bees are aposematically coloured, typically orange and black, warning of their ability to defend themselves with a powerful sting. As such they are models for Batesian mimicry by non-stinging insects such as bee-flies, robber flies and hoverflies, all of which gain a measure of protection by superficially looking and behaving like bees.
Bees are themselves Müllerian mimics of other aposematic insects with the same colour scheme, including wasps, lycid and other beetles, and many butterflies and moths (Lepidoptera) which are themselves distasteful, often through acquiring bitter and poisonous chemicals from their plant food. All the Müllerian mimics, including bees, benefit from the reduced risk of predation that results from their easily recognised warning coloration.
Bees are also mimicked by plants such as the bee orchid which imitates both the appearance and the scent of a female bee; male bees attempt to mate (pseudocopulation) with the furry lip of the flower, thus pollinating it
AS BROOD PARASITES
Brood parasites occur in several bee families including the apid subfamily Nomadinae. Females of these species lack pollen collecting structures (the scopa) and do not construct their own nests. They typically enter the nests of pollen collecting species, and lay their eggs in cells provisioned by the host bee. When the "cuckoo" bee larva hatches, it consumes the host larva's pollen ball, and often the host egg also. In particular, the Arctic bee species, Bombus hyperboreus is an aggressive species that attacks and enslaves other bees of the same subgenus. However, unlike many other bee brood parasites, they have pollen baskets and often collect pollen.
In Southern Africa, hives of African honeybees (A. mellifera scutellata) are being destroyed by parasitic workers of the Cape honeybee, A. m. capensis. These lay diploid eggs ("thelytoky"), escaping normal worker policing, leading to the colony's destruction; the parasites can then move to other hives.
The cuckoo bees in the Bombus subgenus Psithyrus are closely related to, and resemble, their hosts in looks and size. This common pattern gave rise to the ecological principle "Emery's rule". Others parasitize bees in different families, like Townsendiella, a nomadine apid, two species of which are cleptoparasites of the dasypodaid genus Hesperapis, while the other species in the same genus attacks halictid bees.
NOCTURNAL BEES
Four bee families (Andrenidae, Colletidae, Halictidae, and Apidae) contain some species that are crepuscular. Most are tropical or subtropical, but some live in arid regions at higher latitudes. These bees have greatly enlarged ocelli, which are extremely sensitive to light and dark, though incapable of forming images. Some have refracting superposition compound eyes: these combine the output of many elements of their compound eyes to provide enough light for each retinal photoreceptor. Their ability to fly by night enables them to avoid many predators, and to exploit flowers that produce nectar only or also at night.
PREDATORS, PARASITES AND PATHOGENS
Vertebrate predators of bees include bee-eaters, shrikes and flycatchers, which make short sallies to catch insects in flight. Swifts and swallows fly almost continually, catching insects as they go. The honey buzzard attacks bees' nests and eats the larvae. The greater honeyguide interacts with humans by guiding them to the nests of wild bees. The humans break open the nests and take the honey and the bird feeds on the larvae and the wax. Among mammals, predators such as the badger dig up bumblebee nests and eat both the larvae and any stored food.Specialist ambush predators of visitors to flowers include crab spiders, which wait on flowering plants for pollinating insects; predatory bugs, and praying mantises, some of which (the flower mantises of the tropics) wait motionless, aggressive mimics camouflaged as flowers. Beewolves are large wasps that habitually attack bees; the ethologist Niko Tinbergen estimated that a single colony of the beewolf Philanthus triangulum might kill several thousand honeybees in a day: all the prey he observed were honeybees. Other predatory insects that sometimes catch bees include robber flies and dragonflies. Honey bees are affected by parasites including acarine and Varroa mites. However, some bees are believed to have a mutualistic relationship with mites.
RELATIONSHIP WITH HUMANS
IN MYTHOLOGY AND FOLKLORE
Homer's Hymn to Hermes describes three bee-maidens with the power of divination and thus speaking truth, and identifies the food of the gods as honey. Sources associated the bee maidens with Apollo and, until the 1980s, scholars followed Gottfried Hermann (1806) in incorrectly identifying the bee-maidens with the Thriae. Honey, according to a Greek myth, was discovered by a nymph called Melissa ("Bee"); and honey was offered to the Greek gods from Mycenean times. Bees were also associated with the Delphic oracle and the prophetess was sometimes called a bee.
The image of a community of honey bees has been used from ancient to modern times, in Aristotle and Plato; in Virgil and Seneca; in Erasmus and Shakespeare; Tolstoy, and by political and social theorists such as Bernard Mandeville and Karl Marx as a model for human society. In English folklore, bees would be told of important events in the household, in a custom known as "Telling the bees".
IN ART AND LITERATURE
Some of the oldest examples of bees in art are rock paintings in Spain which have been dated to 15,000 BC.
W. B. Yeats's poem The Lake Isle of Innisfree (1888) contains the couplet "Nine bean rows will I have there, a hive for the honey bee, / And live alone in the bee loud glade." At the time he was living in Bedford Park in the West of London. Beatrix Potter's illustrated book The Tale of Mrs Tittlemouse (1910) features Babbity Bumble and her brood (pictured). Kit Williams' treasure hunt book The Bee on the Comb (1984) uses bees and beekeeping as part of its story and puzzle. Sue Monk Kidd's The Secret Life of Bees (2004), and the 2009 film starring Dakota Fanning, tells the story of a girl who escapes her abusive home and finds her way to live with a family of beekeepers, the Boatwrights.
The humorous 2007 animated film Bee Movie used Jerry Seinfeld's first script and was his first work for children; he starred as a bee named Barry B. Benson, alongside Renée Zellweger. Critics found its premise awkward and its delivery tame. Dave Goulson's A Sting in the Tale (2014) describes his efforts to save bumblebees in Britain, as well as much about their biology. The playwright Laline Paull's fantasy The Bees (2015) tells the tale of a hive bee named Flora 717 from hatching onwards.
BEEKEEPING
Humans have kept honey bee colonies, commonly in hives, for millennia. Beekeepers collect honey, beeswax, propolis, pollen, and royal jelly from hives; bees are also kept to pollinate crops and to produce bees for sale to other beekeepers.
Depictions of humans collecting honey from wild bees date to 15,000 years ago; efforts to domesticate them are shown in Egyptian art around 4,500 years ago. Simple hives and smoke were used; jars of honey were found in the tombs of pharaohs such as Tutankhamun. From the 18th century, European understanding of the colonies and biology of bees allowed the construction of the moveable comb hive so that honey could be harvested without destroying the colony. Among Classical Era authors, beekeeping with the use of smoke is described in Aristotle's History of Animals Book 9. The account mentions that bees die after stinging; that workers remove corpses from the hive, and guard it; castes including workers and non-working drones, but "kings" rather than queens; predators including toads and bee-eaters; and the waggle dance, with the "irresistible suggestion" of άpοσειονται ("aroseiontai", it waggles) and παρακολουθούσιν ("parakolouthousin", they watch).
Beekeeping is described in detail by Virgil in his Georgics; it is also mentioned in his Aeneid, and in Pliny's Natural History.
AS COMMERCIAL POLLINATORS
Bees play an important role in pollinating flowering plants, and are the major type of pollinator in many ecosystems that contain flowering plants. It is estimated that one third of the human food supply depends on pollination by insects, birds and bats, most of which is accomplished by bees, whether wild or domesticated. Over the last half century, there has been a general decline in the species richness of wild bees and other pollinators, probably attributable to stress from increased parasites and disease, the use of pesticides, and a general decrease in the number of wild flowers. Climate change probably exacerbates the problem.
Contract pollination has overtaken the role of honey production for beekeepers in many countries. After the introduction of Varroa mites, feral honey bees declined dramatically in the US, though their numbers have since recovered. The number of colonies kept by beekeepers declined slightly, through urbanization, systematic pesticide use, tracheal and Varroa mites, and the closure of beekeeping businesses. In 2006 and 2007 the rate of attrition increased, and was described as colony collapse disorder. In 2010 invertebrate iridescent virus and the fungus Nosema ceranae were shown to be in every killed colony, and deadly in combination. Winter losses increased to about 1/3. Varroa mites were thought to be responsible for about half the losses.
Apart from colony collapse disorder, losses outside the US have been attributed to causes including pesticide seed dressings, using neonicotinoids such as Clothianidin, Imidacloprid and Thiamethoxam. From 2013 the European Union restricted some pesticides to stop bee populations from declining further. In 2014 the Intergovernmental Panel on Climate Change report warned that bees faced increased risk of extinction because of global warming. In 2018 the European Union decided to ban field use of all three major neonicotinoids; they remain permitted in veterinary, greenhouse, and vehicle transport usage.
Farmers have focused on alternative solutions to mitigate these problems. By raising native plants, they provide food for native bee pollinators like Lasioglossum vierecki and L. leucozonium, leading to less reliance on honey bee populations.
AS FOOD PRODUCERS
Honey is a natural product produced by bees and stored for their own use, but its sweetness has always appealed to humans. Before domestication of bees was even attempted, humans were raiding their nests for their honey. Smoke was often used to subdue the bees and such activities are depicted in rock paintings in Spain dated to 15,000 BC.
Honey bees are used commercially to produce honey. They also produce some substances used as dietary supplements with possible health benefits, pollen, propolis, and royal jelly, though all of these can also cause allergic reactions.
AS FOOD (BE BROOD)
Bees are partly considered edible insects. Indigenous people in many countries eat insects, including the larvae and pupae of bees, mostly stingless species. They also gather larvae, pupae and surrounding cells, known as bee brood, for consumption. In the Indonesian dish botok tawon from Central and East Java, bee larvae are eaten as a companion to rice, after being mixed with shredded coconut, wrapped in banana leaves, and steamed.
Bee brood (pupae and larvae) although low in calcium, has been found to be high in protein and carbohydrate, and a useful source of phosphorus, magnesium, potassium, and trace minerals iron, zinc, copper, and selenium. In addition, while bee brood was high in fat, it contained no fat soluble vitamins (such as A, D, and E) but it was a good source of most of the water-soluble B-vitamins including choline as well as vitamin C. The fat was composed mostly of saturated and monounsaturated fatty acids with 2.0% being polyunsaturated fatty acids.
AS ALTERNATIVE MEDICINE
Apitherapy is a branch of alternative medicine that uses honey bee products, including raw honey, royal jelly, pollen, propolis, beeswax and apitoxin (Bee venom). The claim that apitherapy treats cancer, which some proponents of apitherapy make, remains unsupported by evidence-based medicine.
STINGS
The painful stings of bees are mostly associated with the poison gland and the Dufour's gland which are abdominal exocrine glands containing various chemicals. In Lasioglossum leucozonium, the Dufour's Gland mostly contains octadecanolide as well as some eicosanolide. There is also evidence of n-triscosane, n-heptacosane, and 22-docosanolide. However, the secretions of these glands could also be used for nest construction.
WIKIPEDIA
Excited to be participating at CAKE Chicago next weekend ! I will be hosting a table featuring works by Kira Mardikes, myself, and Tim Hogan. The past few weeks I have been assembling a zine/artist book. The images in this work were inspired from reading about the human microbiota. The covers for this piece are made from Fresh Press' rye and corn papers. The images inside are all ink paintings, some of which I've posted here : eburu.tumblr.com/
The first issue of Kira's project Clorofilia Magazine will also be featured, a magazine of plant and ecology inspired comics and articles by artists and farmers.
Tim Hogan's rare book of poems, Perorative Plantings, will also be available. It's a collection of poems written for flowers and plants by two mysterious authors who seem to hail from the Victorian era.
If you are in the city and have never been to Cake, stop by- it's free. Location and hours can be found here: www.cakechicago.com/
Hope to see some you there ! M
Baer's pochard (Aythya baeri) is a diving duck found in eastern Asia. It is a resident bird in North and Central China, formerly bred in southeast Russia and Northeast China, migrating in winter to southern China, Vietnam, Japan, and India. Baer's pochard is a monotypic species. The holotype was collected in middle Amur.
It has a distinctive black head and neck with green gloss not present elsewhere in Aythya. While in poor light, it is likely to look completely black. It is very similar and closely related to the ferruginous duck, and they were previously considered to be a single species; Baer's pochard is differentiated by its white flanks when floating on the water, as well as its larger size and longer, more rounded head.
Its breeding season varies by latitude and environment. The nest, built from sedges, reeds and other plants, is placed among emergent vegetation, usually in shallow water or on small islands or ridges. Its clutch size ranges from 5 to 14. Males usually take on sentry duty, and females take on the responsibility of incubating.
Baer's pochard was once a common species in its range, but is now very rare. The number of mature individuals may be less than 1,000, and its population is still declining. Hunting and habitat loss are considered to be the main reasons. This species has been classified as critically endangered by the IUCN, and listed as a first-class protected animal in China.
Taxonomy
Baer's pochard was first scientifically described in 1863 as Anas baeri by Gustav Radde in his book Reisen im Süden von Ost-Sibirien. The epithet and English common name commemorate the Baltic German naturalist Karl Ernst von Baer. It is also called eastern white-eye, Siberian white-eye, Baer's white-eye and green-headed pochard. The holotype was collected from a small flock in middle Amur during the breeding season. In 1929, when British ornithologist E. C. Stuart Baker studied the birds of British India, he treated Baer's pochard and ferruginous duck as conspecific. However, Chinese ornithologist Tso-hsin Cheng treated them as two distinct species, as they had breeding grounds which did not overlap, and he had seen no evidence of hybridisation. While the species was long thought to have arisen from eastern populations of the ferruginous duck, American ornithologist Paul Johnsgard says its behaviors suggest it may instead be more closely related to the hardhead.
American ornithologist Bradley Curtis Livezey published a phylogenetic study based on morphological data in 1996, in which he proposed his view on the relationship among Tribe Aythyini. Baer's pochard, ferruginous duck, hardhead and Madagascar pochard are classified in subgenus Nyroca (the "white-eyes"), intrasubgenus relationship is unclear, but the ferruginous duck was suggested to be the sister group of Baer's pochard. The subgenus Aythya (the "scapu", including New Zealand Scaup, ring-necked duck, tufted duck, greater scaup and lesser scaup) is the sister group of subgenus Nyroca. The subgenus Aristonetta (the "redheads", including the common pochard, canvasback and redhead) is the sister group of all other pochards.
Two molecular phylogenetic studies on Anseriformes or Anatidae were published in 2000s, some mitochondrial genes were sequenced, but Baer's pochard was absent in both of them. The mitochondrial genome of Baer's pochard was sequenced and published in 2021. Molecular phylogenetic studies determined the relationships among Baer's pochard and other closely related species:
Tribe. Aythyini
Aythya
Baer's pochard Aythya baeri
Tufted Duck A. fuligula
Common pochard A. ferina
Redhead A. americana
Netta
Red-crested pochard Netta rufina
Asarcornis
White-winged duck Asarcornis scutulata
Description
The Baer's pochard is 41–47 cm (16–19 in) long with a 70–79 cm (28–31 in) wingspan. The male is slightly larger, weighing on average 500–730 g (18–26 oz), wings lengthed 18.6–20.3 cm (7.3–8.0 in), tail at 53–60 mm (2.1–2.4 in), and culmen at 38–44 mm (1.5–1.7 in). Relatively, the female weighing on average 590–655 g (20.8–23.1 oz), wings lengthed 19.1–20.5 cm (7.5–8.1 in), tail at 51–64 mm (2.0–2.5 in), and culmen at 40–44 mm (1.6–1.7 in). Both male and female's tarsometatarsus lengthed 33–34.7 mm (1.30–1.37 in).
Breeding male has a black head and neck with green gloss, white or paler yellow eyes, blackish-brown back, dark chestnut breast, white or light chestnut flanks and a short and low tail. The green gloss on its head is unique among Aythya. While it is likely to look completely black in poor light. Female has a dark brown head and neck that blend into the chestnut-brown breast and flanks. Eclipse and first-winter male resembles female, but retain the white eyes, while female has brown eyes. Both male and female have wide white speculum feathers, white vent-side, dark-grey bill, black nail and dark-grey tarsometatarsus.
It is similar to its close relative, the ferruginous duck (A. nyroca), both have white vent-side and iris in males, black nail, and wide white speculum feathers. Although Baer's pochard is bigger, has a longer head, body and bill. Unlike the ferruginous duck's tall and triangular head, Baer's pochard has a more rounded head and a flatter forehead. The white part on the belly extends to its flanks in Baer's pochard, which is visible when floating on the water, while the ferruginous duck has a smaller white part on its belly. The female Baer's pochard has a distinctly bright chestnut spot at the lore, which is absent in ferruginous duck.
Baer's pochard is usually a quieter duck, but during its courtship display, both sexes give harsh graaaak. Females may give kura kura kura and males may give kuro kuro at other times.
Distribution
Baer's pochard traditionally bred in the Amur and Ussuri basins in Northeast China and the southeastern Russian Far East. In recent years, it has also colonised North China and Central China. It winters in most areas south of the Yellow River in China, Taiwan, Japan, Bangladesh, India, North Korea, Laos, Myanmar, Nepal, Thailand and Vietnam, and occasionally appears in Bhutan, South Korea, Philippines or Pakistan as a rare vagrant. It leaves its wintering grounds by mid-March and returns to them by mid-October or early November.
The species has become extremely rare in its traditional breeding areas, and since 2010, there have been no confirmed breeding reports in all sites north of Beijing. However, the numbers recorded during the breeding season are smaller than those recorded in winter, so there may still be unknown breeding sites. For example, there are some doubtful breeding reports in the Chinese part of Lake Khanka, the Russian part of Lake Khasan, and the Muraviovka Park [ru]. Since 2012, new breeding sites have been discovered in several provinces of China, including Hebei, Hubei and Jiangxi; the latter two cities are far from traditional breeding sites in the Amur and Ussuri basins.[1] In these new breeding areas, warmer climate conditions provide a longer breeding season (about twice as long as in the Amur and Ussuri basins) which allows birds to lay a replacement clutch if their first clutch fails. Baer's pochard is no longer migratory in central and eastern China.
The wintering grounds have also contracted significantly in recent years. Since at least the winter of 2010-2011, Baer's pochard no longer winters in any site outside mainland China, except as a vagrant. In its wintering grounds in mainland China, the population has also declined severely, by more than 99%.
Behaviour and ecology
Baer's pochard is a shy species, that inhabit open, slow-flowing lakes, swamps and ponds. It breeds around lakes with rich aquatic vegetation, nesting in dense grass, flooded tussock meadows, or flooded shrubby meadows. In winter, it forms large flocks on large and open freshwater lakes and reservoirs with other pochards. It has strong wings, and can flyor walk at high speeds. It is also good at diving and swimming, and can quickly take off from the water when threatened or disturbed. In migrating season, they form small groups of more than 10 or dozens of birds, flying at low altitudes in wedge-shaped formations. During winter, Baer's pochard sleeps during the day, leaves for unknown feeding sites with other ducks in the dusk, and returns before dawn. Little is known about their diet beyond aquatic plants, grass seeds and molluscs.
Breeding
Baer's pochard appears to have a monogamous mating system, at least within a breeding season. In traditional breeding grounds in northeastern China, Baer's pochard gathers in gaps in the ice before it completely thawed. After the ice season, it gathers on the large, open lakes. They breed from mid-to-late May. While in Fuhe Wetland in Wuhan, Hubei, Baer's pochard gathers in large groups on the open lakes before breeding season. It is divided into small groups in mid-April, in which they will courting and mating. During courtship, the male swims around the female, repeatedly nods his head up and down. When other males approach, it swims toward them quickly to drive them away, but there is no violent fight between them. The female also nods her head in response. When the male approaches, the female straightens her neck and lowers her head to the water. He then climbs onto her body and bites her nape feathers to mate. After the mating, the male and female leave the flock for nesting.
Baer's pochard's nest is circular cylindrical, located among emergent vegetation, usually in shallow water or on small islands or ridges. The nest is made of sedges, reeds and other plants collected from the immediate vicinity, lined with a layer of down. Its clutch ranged from 5 to 14, with an average of 9.7. Males usually take on sentry duty at about 10 meters from the nest during hatching. Females leave the nest to forage 2–3 times a day, usually during 6:00-20:00, and lasted for 27–240 min. They cover the eggs with nest materials during forging, and place them onto their back when coming back. If water levels are elevated by heavy rainfall or human activity, females increase the height of the nest to avoid flooding. During the hottest days, females often stand on the nest and shelter eggs from the strong sunlight, whilst allowing circulation of air around them. Females also take water into their plumage and use it to cool the eggs. The incubation lasted for 23-26 days.
Studies have shown that the nest survival rate[note 3] of Baer's pochards is about 14–45%, and each clutch may lose one to nine eggs. About 20-30% of eggs hatched successfully, and 3–16 young fledged per nest. There are three major reasons contributing to the failure, including nest desertion (abandoned by parents), nest predation (mainly by Siberian Weasels) and flooding. The proportion of these causes varies among years. In addition, most of the breeding sites in Wuhan are Crayfish farms, the farming work and eggs collection may also be hindrances.
Biological interaction
Incomplete inter- and intra-specific brood parasitism were found in Baer's pochard. In Xianghai National Nature Reserve [zh], Baer's pochards could parasitize gadwall and common pochard, and may be parasitized by common pochard. In Wuhan, Baer's pochard shares breeding sites with cotton teal, eastern spot-billed duck and mallard. Interspecific brood parasitism was not observed. Intraspecific parasitic was found in Wuhan. If caught, the parasite will get attacked by the host.
Baer's pochard has hybridized with lesser scaup, common pochard, ferruginous duck, New Zealand scaup, chestnut teal and wood duck in captivity. Ferruginous duck was observed displaying to Baer's pochards several times in China and South Korea. Some individuals showed mixed characteristics of common, ferruginous and Baer's pochards, so they may be currently hybridising in the wild. The Baer's pochard has declined sharply in recent years, but the ferruginous and common pochard has expanded their breeding grounds, and even to the core areas of Baer's pochard's, which makes the hypothesis possible.
The research on its gut microbiota showed that the richest microorganism phyla of Baer's pochard are Bacillota, Pseudomonadota and Bacteroidota, which were consistent with those of the domestic goose, duck and chicken. The gut microbiota in diarrheic Baer's pochard is low in diversity, and the species were also significantly different from healthy individuals. Most species in reduced numbers are thought to be intestinal beneficial bacteria.
Threats and protection
Baer's pochard was once a common species in its range, but is now very rare. Mature individuals may be less than 1,000. According to records in China, there were 16,792 wintering individuals from 1986/87 to 1992/93, but only 3,472 from 1993/94 to 1998/99, and only 2,131 from 2002/03 to 2010/11. Bangladesh had more than 3,000 in 1996, India had more than 1,400 in 1995 and 1997, Myanmar had about 500-1,000 in the 1990s, and 596 were counted in 1998 in Thailand. While by 1999/00-2004/05, only 719 were counted in all wintering grounds except China, and only 48 individuals in 2005/06-2010/11. In China, hunting and habitat loss were considered to be the main threats. From 336 to 4,803 pochards were hunted annually in Honghu, Hubei from 1981 to 1997; in areas near Rudong County, maybe 3,000 are hunted every year. The wintering grounds have been significantly changed due to water pollution, fishing management, changes in aquatic plants, and the changing ecology of many wetlands in the Yangtze River floodplain. Factors in breeding and migrating grounds may also have contributed to its decline. The global decline shows no sign of slowing or stopping.
Baer's pochard was formerly classified as a vulnerable species by the IUCN. Recent research has shown that its numbers are decreasing more and more rapidly, and it was consequently uplisted to endangered status in 2008. In 2012, it was further uplisted to critically endangered. In 2014, the East Asian–Australasian Flyway Partnership (EAAFP) drafted the Baer's Pochard Task Force and it was endorsed in Jan 2015. Baer's pochard was listed as a first-class protected animal in China by 2021. In 2022, media reports state that the first captive population in China was established in the Beijing Zoo, with totally 54 individuals. It is planned to be further expanded and used for reintroduction.
A study published in 2022 showed that most breeding sites (81.8%) and suitable habitats (94%) are not located in protected areas, and overlap with large cities. Current protected areas may be less effective for the conservation under predicted global climate change, closely coordinated cross-border cooperation would be critical for Baer's pochard
iss056e097340 (July 18, 2018) --- NASA astronaut Drew Feustel works inside the Microgravity Science Glovebox inspecting mice being observed as part of the Rodent Research-7 experiment. Feustel measured the rodent's breathing and mass for the study that examines how the space environment affects the community of microoganisms in the gastrointestinal tract of mice (also known as the microbiota). It also looks at microgravity’s effects on multiple physiological systems known to be affected by the microbiota, including the gastrointestinal, immune, metabolic, circadian, and sleep systems. These studies help explain mechanisms underlying interactions between these systems and the role of the microbiota in these interactions.
is what we have here
you can put your finger on the line exactly _where_ and _when_ an ancient tidewater Stromatolite Mound was smothered by catastrophic Sudbury Impact Layer, 1.85 billion years ago
double zoom in or View Large to see a roiling carpet of shards, spherules and fine material that scoured matted cyanobacteria when Asteroidal Armageddon swept through the Thunder Bay area; this site is 675 km away from the Sudbury epicenter to the world's best exposed large asteroid impact crater (200 km wide and 6 km deep) when unfolded after being squished into a burrito shape by ancient plate tectonics.
The Sudbury impacter laid a stupefying "whupping" at least a continent wide upon ancient Earth.
en.wikipedia.org/wiki/Sudbury_Basin
more images of the Sudbury Impact Crater melt and farflung Sudbury Impact Layer are in my Rocks From Space album
Widespread evidence far away to the west of Sudbury shows that the asteroid impact terminated the deposition of an extensive basin of sedimentary iron formation. It also left a mid-continent rift zone, to be filled in by Rove Formation shales, bereft of microbiota for an extended period of time.
Water-sprayed 2 ft (0.6 m) Thunder Bay area rock sample in the back yard of Rox Rock Shop in Westport ON, destined for slabbing and polishing. Store is geotagged, should anyone want to acquire a unique biogeochemical slice of 'deep time'.
Bees are flying insects closely related to wasps and ants, known for their role in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyletic lineage within the superfamily Apoidea. They are presently considered a clade, called Anthophila. There are over 16,000 known species of bees in seven recognized biological families. Some species – including honey bees, bumblebees, and stingless bees – live socially in colonies while some species – including mason bees, carpenter bees, leafcutter bees, and sweat bees – are solitary.
Bees are found on every continent except for Antarctica, in every habitat on the planet that contains insect-pollinated flowering plants. The most common bees in the Northern Hemisphere are the Halictidae, or sweat bees, but they are small and often mistaken for wasps or flies. Bees range in size from tiny stingless bee species, whose workers are less than 2 millimetres long, to Megachile pluto, the largest species of leafcutter bee, whose females can attain a length of 39 millimetres.
Bees feed on nectar and pollen, the former primarily as an energy source and the latter primarily for protein and other nutrients. Most pollen is used as food for their larvae. Vertebrate predators of bees include birds such as bee-eaters; insect predators include beewolves and dragonflies.
Bee pollination is important both ecologically and commercially, and the decline in wild bees has increased the value of pollination by commercially managed hives of honey bees. The analysis of 353 wild bee and hoverfly species across Britain from 1980 to 2013 found the insects have been lost from a quarter of the places they inhabited in 1980.
Human beekeeping or apiculture has been practised for millennia, since at least the times of Ancient Egypt and Ancient Greece. Bees have appeared in mythology and folklore, through all phases of art and literature from ancient times to the present day, although primarily focused in the Northern Hemisphere where beekeeping is far more common.
EVOLUTION
The ancestors of bees were wasps in the family Crabronidae, which were predators of other insects. The switch from insect prey to pollen may have resulted from the consumption of prey insects which were flower visitors and were partially covered with pollen when they were fed to the wasp larvae. This same evolutionary scenario may have occurred within the vespoid wasps, where the pollen wasps evolved from predatory ancestors. Until recently, the oldest non-compression bee fossil had been found in New Jersey amber, Cretotrigona prisca of Cretaceous age, a corbiculate bee. A bee fossil from the early Cretaceous (~100 mya), Melittosphex burmensis, is considered "an extinct lineage of pollen-collecting Apoidea sister to the modern bees". Derived features of its morphology (apomorphies) place it clearly within the bees, but it retains two unmodified ancestral traits (plesiomorphies) of the legs (two mid-tibial spurs, and a slender hind basitarsus), showing its transitional status. By the Eocene (~45 mya) there was already considerable diversity among eusocial bee lineages.
The highly eusocial corbiculate Apidae appeared roughly 87 Mya, and the Allodapini (within the Apidae) around 53 Mya. The Colletidae appear as fossils only from the late Oligocene (~25 Mya) to early Miocene. The Melittidae are known from Palaeomacropis eocenicus in the Early Eocene. The Megachilidae are known from trace fossils (characteristic leaf cuttings) from the Middle Eocene. The Andrenidae are known from the Eocene-Oligocene boundary, around 34 Mya, of the Florissant shale. The Halictidae first appear in the Early Eocene with species found in amber. The Stenotritidae are known from fossil brood cells of Pleistocene age.
COEVOLUTION
The earliest animal-pollinated flowers were shallow, cup-shaped blooms pollinated by insects such as beetles, so the syndrome of insect pollination was well established before the first appearance of bees. The novelty is that bees are specialized as pollination agents, with behavioral and physical modifications that specifically enhance pollination, and are the most efficient pollinating insects. In a process of coevolution, flowers developed floral rewards such as nectar and longer tubes, and bees developed longer tongues to extract the nectar. Bees also developed structures known as scopal hairs and pollen baskets to collect and carry pollen. The location and type differ among and between groups of bees. Most species have scopal hairs on their hind legs or on the underside of their abdomens. Some species in the family Apidae have pollen baskets on their hind legs, while very few lack these and instead collect pollen in their crops. The appearance of these structures drove the adaptive radiation of the angiosperms, and, in turn, bees themselves. Bees coevolved not only with flowers but it is believed that some species coevolved with mites. Some provide tufts of hairs called acarinaria that appear to provide lodgings for mites; in return, it is believed that mites eat fungi that attack pollen, so the relationship in this case may be mutualistc.
CHARACTERISTICS
Bees differ from closely related groups such as wasps by having branched or plume-like setae (hairs), combs on the forelimbs for cleaning their antennae, small anatomical differences in limb structure, and the venation of the hind wings; and in females, by having the seventh dorsal abdominal plate divided into two half-plates.
Bees have the following characteristics:
A pair of large compound eyes which cover much of the surface of the head. Between and above these are three small simple eyes (ocelli) which provide information on light intensity.
The antennae usually have 13 segments in males and 12 in females, and are geniculate, having an elbow joint part way along. They house large numbers of sense organs that can detect touch (mechanoreceptors), smell and taste; and small, hairlike mechanoreceptors that can detect air movement so as to "hear" sounds.
The mouthparts are adapted for both chewing and sucking by having both a pair of mandibles and a long proboscis for sucking up nectar.
The thorax has three segments, each with a pair of robust legs, and a pair of membranous wings on the hind two segments. The front legs of corbiculate bees bear combs for cleaning the antennae, and in many species the hind legs bear pollen baskets, flattened sections with incurving hairs to secure the collected pollen. The wings are synchronised in flight, and the somewhat smaller hind wings connect to the forewings by a row of hooks along their margin which connect to a groove in the forewing.
The abdomen has nine segments, the hindermost three being modified into the sting.
The largest species of bee is thought to be Wallace's giant bee Megachile pluto, whose females can attain a length of 39 millimetres. The smallest species may be dwarf stingless bees in the tribe Meliponini whose workers are less than 2 millimetres in length.
SOCIALITY
HAPLODIPLOID BREEDING SYSTEM
According to inclusive fitness theory, organisms can gain fitness not just through increasing their own reproductive output, but also that of close relatives. In evolutionary terms, individuals should help relatives when Cost < Relatedness * Benefit. The requirements for eusociality are more easily fulfilled by haplodiploid species such as bees because of their unusual relatedness structure.
In haplodiploid species, females develop from fertilized eggs and males from unfertilized eggs. Because a male is haploid (has only one copy of each gene), his daughters (which are diploid, with two copies of each gene) share 100% of his genes and 50% of their mother's. Therefore, they share 75% of their genes with each other. This mechanism of sex determination gives rise to what W. D. Hamilton termed "supersisters", more closely related to their sisters than they would be to their own offspring. Workers often do not reproduce, but they can pass on more of their genes by helping to raise their sisters (as queens) than they would by having their own offspring (each of which would only have 50% of their genes), assuming they would produce similar numbers. This unusual situation has been proposed as an explanation of the multiple (at least 9) evolutions of eusociality within Hymenoptera.
Haplodiploidy is neither necessary nor sufficient for eusociality. Some eusocial species such as termites are not haplodiploid. Conversely, all bees are haplodiploid but not all are eusocial, and among eusocial species many queens mate with multiple males, creating half-sisters that share only 25% of each-other's genes. But, monogamy (queens mating singly) is the ancestral state for all eusocial species so far investigated, so it is likely that haplodiploidy contributed to the evolution of eusociality in bees.
EUSOCIALIT
Bees may be solitary or may live in various types of communities. Eusociality appears to have originated from at least three independent origins in halictid bees. The most advanced of these are species with eusocial colonies; these are characterised by cooperative brood care and a division of labour into reproductive and non-reproductive adults, plus overlapping generations. This division of labour creates specialized groups within eusocial societies which are called castes. In some species, groups of cohabiting females may be sisters, and if there is a division of labour within the group, they are considered semisocial. The group is called eusocial if, in addition, the group consists of a mother (the queen) and her daughters (workers). When the castes are purely behavioural alternatives, with no morphological differentiation other than size, the system is considered primitively eusocial, as in many paper wasps; when the castes are morphologically discrete, the system is considered highly eusocial.True honey bees (genus Apis, of which seven species are currently recognized) are highly eusocial, and are among the best known insects. Their colonies are established by swarms, consisting of a queen and several hundred workers. There are 29 subspecies of one of these species, Apis mellifera, native to Europe, the Middle East, and Africa. Africanized bees are a hybrid strain of A. mellifera that escaped from experiments involving crossing European and African subspecies; they are extremely defensive.[Stingless bees are also highly eusocial. They practise mass provisioning, with complex nest architecture and perennial colonies also established via swarming.
Many bumblebees are eusocial, similar to the eusocial Vespidae such as hornets in that the queen initiates a nest on her own rather than by swarming. Bumblebee colonies typically have from 50 to 200 bees at peak population, which occurs in mid to late summer. Nest architecture is simple, limited by the size of the pre-existing nest cavity, and colonies rarely last more than a year. In 2011, the International Union for Conservation of Nature set up the Bumblebee Specialist Group to review the threat status of all bumblebee species worldwide using the IUCN Red List criteria.
There are many more species of primitively eusocial than highly eusocial bees, but they have been studied less often. Most are in the family Halictidae, or "sweat bees". Colonies are typically small, with a dozen or fewer workers, on average. Queens and workers differ only in size, if at all. Most species have a single season colony cycle, even in the tropics, and only mated females hibernate. A few species have long active seasons and attain colony sizes in the hundreds, such as Halictus hesperus. Some species are eusocial in parts of their range and solitary in others, or have a mix of eusocial and solitary nests in the same population. The orchid bees (Apidae) include some primitively eusocial species with similar biology. Some allodapine bees (Apidae) form primitively eusocial colonies, with progressive provisioning: a larva's food is supplied gradually as it develops, as is the case in honey bees and some bumblebees.
SOLITARY AND COMMUNAL BEES
Most other bees, including familiar insects such as carpenter bees, leafcutter bees and mason bees are solitary in the sense that every female is fertile, and typically inhabits a nest she constructs herself. There is no division of labor so these nests lack queens and worker bees for these species. Solitary bees typically produce neither honey nor beeswax. Bees collect pollen to feed their young, and have the necessary adaptations to do this. However, certain wasp species such as pollen wasps have similar behaviours, and a few species of bee scavenge from carcases to feed their offspring. Solitary bees are important pollinators; they gather pollen to provision their nests with food for their brood. Often it is mixed with nectar to form a paste-like consistency. Some solitary bees have advanced types of pollen-carrying structures on their bodies. Very few species of solitary bee are being cultured for commercial pollination. Most of these species belong to a distinct set of genera which are commonly known by their nesting behavior or preferences, namely: carpenter bees, sweat bees, mason bees, plasterer bees, squash bees, dwarf carpenter bees, leafcutter bees, alkali bees and digger bees.Most solitary bees nest in the ground in a variety of soil textures and conditions while others create nests in hollow reeds or twigs, holes in wood. The female typically creates a compartment (a "cell") with an egg and some provisions for the resulting larva, then seals it off. A nest may consist of numerous cells. When the nest is in wood, usually the last (those closer to the entrance) contain eggs that will become males. The adult does not provide care for the brood once the egg is laid, and usually dies after making one or more nests. The males typically emerge first and are ready for mating when the females emerge. Solitary bees are either stingless or very unlikely to sting (only in self-defense, if ever). While solitary, females each make individual nests. Some species, such as the European mason bee Hoplitis anthocopoides, and the Dawson's Burrowing bee, Amegilla dawsoni, are gregarious, preferring to make nests near others of the same species, and giving the appearance of being social. Large groups of solitary bee nests are called aggregations, to distinguish them from colonies. In some species, multiple females share a common nest, but each makes and provisions her own cells independently. This type of group is called "communal" and is not uncommon. The primary advantage appears to be that a nest entrance is easier to defend from predators and parasites when multiple females use that same entrance regularly
BIOLOGY
LIFE CYCLE
The life cycle of a bee, be it a solitary or social species, involves the laying of an egg, the development through several moults of a legless larva, a pupation stage during which the insect undergoes complete metamorphosis, followed by the emergence of a winged adult. Most solitary bees and bumble bees in temperate climates overwinter as adults or pupae and emerge in spring when increasing numbers of flowering plants come into bloom. The males usually emerge first and search for females with which to mate. The sex of a bee is determined by whether or not the egg is fertilised; after mating, a female stores the sperm, and determines which sex is required at the time each individual egg is laid, fertilised eggs producing female offspring and unfertilised eggs, males. Tropical bees may have several generations in a year and no diapause stage.
The egg is generally oblong, slightly curved and tapering at one end. Solitary bees, lay each egg in a separate cell with a supply of mixed pollen and nectar next to it. This may be rolled into a pellet or placed in a pile and is known as mass provisioning. Social bee species provision progressively, that is, they feed the larva regularly while it grows. The nest varies from a hole in the ground or in wood, in solitary bees, to a substantial structure with wax combs in bumblebees and honey bees.
In most species, larvae are whitish grubs, roughly oval and bluntly-pointed at both ends. They have 15 segments and spiracles in each segment for breathing. They have no legs but move within the cell, helped by tubercles on their sides. They have short horns on the head, jaws for chewing food and an appendage on either side of the mouth tipped with a bristle. There is a gland under the mouth that secretes a viscous liquid which solidifies into the silk they use to produce a cocoon. The cocoon is semi-transparent and the pupa can be seen through it. Over the course of a few days, the larva undergoes metamorphosis into a winged adult. When ready to emerge, the adult splits its skin dorsally and climbs out of the exuviae and breaks out of the cell.
FLIGHT
Antoine Magnan's 1934 book Le vol des insectes, says that he and André Sainte-Laguë had applied the equations of air resistance to insects and found that their flight could not be explained by fixed-wing calculations, but that "One shouldn't be surprised that the results of the calculations don't square with reality". This has led to a common misconception that bees "violate aerodynamic theory". In fact it merely confirms that bees do not engage in fixed-wing flight, and that their flight is explained by other mechanics, such as those used by helicopters. In 1996 it was shown that vortices created by many insects' wings helped to provide lift. High-speed cinematography and robotic mock-up of a bee wing showed that lift was generated by "the unconventional combination of short, choppy wing strokes, a rapid rotation of the wing as it flops over and reverses direction, and a very fast wing-beat frequency". Wing-beat frequency normally increases as size decreases, but as the bee's wing beat covers such a small arc, it flaps approximately 230 times per second, faster than a fruitfly (200 times per second) which is 80 times smaller.
NAVIGATION, COMMUNICATION AND FINDING FOOD
The ethologist Karl von Frisch studied navigation in the honey bee. He showed that honey bees communicate by the waggle dance, in which a worker indicates the location of a food source to other workers in the hive. He demonstrated that bees can recognize a desired compass direction in three different ways: by the sun, by the polarization pattern of the blue sky, and by the earth's magnetic field. He showed that the sun is the preferred or main compass; the other mechanisms are used under cloudy skies or inside a dark beehive. Bees navigate using spatial memory with a "rich, map-like organization".
DIGESTION
The gut of bees is relatively simple, but multiple metabolic strategies exist in the gut microbiota. Pollinating bees consume nectar and pollen, which require different digestion strategies by somewhat specialized bacteria. While nectar is a liquid of mostly monosaccharide sugars and so easily absorbed, pollen contains complex polysaccharides: branching pectin and hemicellulose. Approximately five groups of bacteria are involved in digestion. Three groups specialize in simple sugars (Snodgrassella and two groups of Lactobacillus), and two other groups in complex sugars (Gilliamella and Bifidobacterium). Digestion of pectin and hemicellulose is dominated by bacterial clades Gilliamella and Bifidobacterium respectively. Bacteria that cannot digest polysaccharides obtain enzymes from their neighbors, and bacteria that lack certain amino acids do the same, creating multiple ecological niches.
Although most bee species are nectarivorous and palynivorous, some are not. Particularly unusual are vulture bees in the genus Trigona, which consume carrion and wasp brood, turning meat into a honey-like substance.
ECOLOGY
FLORAL RELATIONSHIPS
Most bees are polylectic (generalist) meaning they collect pollen from a range of flowering plants, but some are oligoleges (specialists), in that they only gather pollen from one or a few species or genera of closely related plants. Specialist pollinators also include bee species which gather floral oils instead of pollen, and male orchid bees, which gather aromatic compounds from orchids (one of the few cases where male bees are effective pollinators). Bees are able to sense the presence of desirable flowers through ultraviolet patterning on flowers, floral odors, and even electromagnetic fields. Once landed, a bee then uses nectar quality and pollen taste to determine whether to continue visiting similar flowers.
In rare cases, a plant species may only be effectively pollinated by a single bee species, and some plants are endangered at least in part because their pollinator is also threatened. But, there is a pronounced tendency for oligolectic bees to be associated with common, widespread plants visited by multiple pollinator species. For example, the creosote bush in the arid parts of the United States southwest is associated with some 40 oligoleges.
AS MIMICS AND MODELS
Many bees are aposematically coloured, typically orange and black, warning of their ability to defend themselves with a powerful sting. As such they are models for Batesian mimicry by non-stinging insects such as bee-flies, robber flies and hoverflies, all of which gain a measure of protection by superficially looking and behaving like bees.
Bees are themselves Müllerian mimics of other aposematic insects with the same colour scheme, including wasps, lycid and other beetles, and many butterflies and moths (Lepidoptera) which are themselves distasteful, often through acquiring bitter and poisonous chemicals from their plant food. All the Müllerian mimics, including bees, benefit from the reduced risk of predation that results from their easily recognised warning coloration.
Bees are also mimicked by plants such as the bee orchid which imitates both the appearance and the scent of a female bee; male bees attempt to mate (pseudocopulation) with the furry lip of the flower, thus pollinating it
AS BROOD PARASITES
Brood parasites occur in several bee families including the apid subfamily Nomadinae. Females of these species lack pollen collecting structures (the scopa) and do not construct their own nests. They typically enter the nests of pollen collecting species, and lay their eggs in cells provisioned by the host bee. When the "cuckoo" bee larva hatches, it consumes the host larva's pollen ball, and often the host egg also. In particular, the Arctic bee species, Bombus hyperboreus is an aggressive species that attacks and enslaves other bees of the same subgenus. However, unlike many other bee brood parasites, they have pollen baskets and often collect pollen.
In Southern Africa, hives of African honeybees (A. mellifera scutellata) are being destroyed by parasitic workers of the Cape honeybee, A. m. capensis. These lay diploid eggs ("thelytoky"), escaping normal worker policing, leading to the colony's destruction; the parasites can then move to other hives.
The cuckoo bees in the Bombus subgenus Psithyrus are closely related to, and resemble, their hosts in looks and size. This common pattern gave rise to the ecological principle "Emery's rule". Others parasitize bees in different families, like Townsendiella, a nomadine apid, two species of which are cleptoparasites of the dasypodaid genus Hesperapis, while the other species in the same genus attacks halictid bees.
NOCTURNAL BEES
Four bee families (Andrenidae, Colletidae, Halictidae, and Apidae) contain some species that are crepuscular. Most are tropical or subtropical, but some live in arid regions at higher latitudes. These bees have greatly enlarged ocelli, which are extremely sensitive to light and dark, though incapable of forming images. Some have refracting superposition compound eyes: these combine the output of many elements of their compound eyes to provide enough light for each retinal photoreceptor. Their ability to fly by night enables them to avoid many predators, and to exploit flowers that produce nectar only or also at night.
PREDATORS, PARASITES AND PATHOGENS
Vertebrate predators of bees include bee-eaters, shrikes and flycatchers, which make short sallies to catch insects in flight. Swifts and swallows fly almost continually, catching insects as they go. The honey buzzard attacks bees' nests and eats the larvae. The greater honeyguide interacts with humans by guiding them to the nests of wild bees. The humans break open the nests and take the honey and the bird feeds on the larvae and the wax. Among mammals, predators such as the badger dig up bumblebee nests and eat both the larvae and any stored food.Specialist ambush predators of visitors to flowers include crab spiders, which wait on flowering plants for pollinating insects; predatory bugs, and praying mantises, some of which (the flower mantises of the tropics) wait motionless, aggressive mimics camouflaged as flowers. Beewolves are large wasps that habitually attack bees; the ethologist Niko Tinbergen estimated that a single colony of the beewolf Philanthus triangulum might kill several thousand honeybees in a day: all the prey he observed were honeybees. Other predatory insects that sometimes catch bees include robber flies and dragonflies. Honey bees are affected by parasites including acarine and Varroa mites. However, some bees are believed to have a mutualistic relationship with mites.
RELATIONSHIP WITH HUMANS
IN MYTHOLOGY AND FOLKLORE
Homer's Hymn to Hermes describes three bee-maidens with the power of divination and thus speaking truth, and identifies the food of the gods as honey. Sources associated the bee maidens with Apollo and, until the 1980s, scholars followed Gottfried Hermann (1806) in incorrectly identifying the bee-maidens with the Thriae. Honey, according to a Greek myth, was discovered by a nymph called Melissa ("Bee"); and honey was offered to the Greek gods from Mycenean times. Bees were also associated with the Delphic oracle and the prophetess was sometimes called a bee.
The image of a community of honey bees has been used from ancient to modern times, in Aristotle and Plato; in Virgil and Seneca; in Erasmus and Shakespeare; Tolstoy, and by political and social theorists such as Bernard Mandeville and Karl Marx as a model for human society. In English folklore, bees would be told of important events in the household, in a custom known as "Telling the bees".
IN ART AND LITERATURE
Some of the oldest examples of bees in art are rock paintings in Spain which have been dated to 15,000 BC.
W. B. Yeats's poem The Lake Isle of Innisfree (1888) contains the couplet "Nine bean rows will I have there, a hive for the honey bee, / And live alone in the bee loud glade." At the time he was living in Bedford Park in the West of London. Beatrix Potter's illustrated book The Tale of Mrs Tittlemouse (1910) features Babbity Bumble and her brood (pictured). Kit Williams' treasure hunt book The Bee on the Comb (1984) uses bees and beekeeping as part of its story and puzzle. Sue Monk Kidd's The Secret Life of Bees (2004), and the 2009 film starring Dakota Fanning, tells the story of a girl who escapes her abusive home and finds her way to live with a family of beekeepers, the Boatwrights.
The humorous 2007 animated film Bee Movie used Jerry Seinfeld's first script and was his first work for children; he starred as a bee named Barry B. Benson, alongside Renée Zellweger. Critics found its premise awkward and its delivery tame. Dave Goulson's A Sting in the Tale (2014) describes his efforts to save bumblebees in Britain, as well as much about their biology. The playwright Laline Paull's fantasy The Bees (2015) tells the tale of a hive bee named Flora 717 from hatching onwards.
BEEKEEPING
Humans have kept honey bee colonies, commonly in hives, for millennia. Beekeepers collect honey, beeswax, propolis, pollen, and royal jelly from hives; bees are also kept to pollinate crops and to produce bees for sale to other beekeepers.
Depictions of humans collecting honey from wild bees date to 15,000 years ago; efforts to domesticate them are shown in Egyptian art around 4,500 years ago. Simple hives and smoke were used; jars of honey were found in the tombs of pharaohs such as Tutankhamun. From the 18th century, European understanding of the colonies and biology of bees allowed the construction of the moveable comb hive so that honey could be harvested without destroying the colony. Among Classical Era authors, beekeeping with the use of smoke is described in Aristotle's History of Animals Book 9. The account mentions that bees die after stinging; that workers remove corpses from the hive, and guard it; castes including workers and non-working drones, but "kings" rather than queens; predators including toads and bee-eaters; and the waggle dance, with the "irresistible suggestion" of άpοσειονται ("aroseiontai", it waggles) and παρακολουθούσιν ("parakolouthousin", they watch).
Beekeeping is described in detail by Virgil in his Georgics; it is also mentioned in his Aeneid, and in Pliny's Natural History.
AS COMMERCIAL POLLINATORS
Bees play an important role in pollinating flowering plants, and are the major type of pollinator in many ecosystems that contain flowering plants. It is estimated that one third of the human food supply depends on pollination by insects, birds and bats, most of which is accomplished by bees, whether wild or domesticated. Over the last half century, there has been a general decline in the species richness of wild bees and other pollinators, probably attributable to stress from increased parasites and disease, the use of pesticides, and a general decrease in the number of wild flowers. Climate change probably exacerbates the problem.
Contract pollination has overtaken the role of honey production for beekeepers in many countries. After the introduction of Varroa mites, feral honey bees declined dramatically in the US, though their numbers have since recovered. The number of colonies kept by beekeepers declined slightly, through urbanization, systematic pesticide use, tracheal and Varroa mites, and the closure of beekeeping businesses. In 2006 and 2007 the rate of attrition increased, and was described as colony collapse disorder. In 2010 invertebrate iridescent virus and the fungus Nosema ceranae were shown to be in every killed colony, and deadly in combination. Winter losses increased to about 1/3. Varroa mites were thought to be responsible for about half the losses.
Apart from colony collapse disorder, losses outside the US have been attributed to causes including pesticide seed dressings, using neonicotinoids such as Clothianidin, Imidacloprid and Thiamethoxam. From 2013 the European Union restricted some pesticides to stop bee populations from declining further. In 2014 the Intergovernmental Panel on Climate Change report warned that bees faced increased risk of extinction because of global warming. In 2018 the European Union decided to ban field use of all three major neonicotinoids; they remain permitted in veterinary, greenhouse, and vehicle transport usage.
Farmers have focused on alternative solutions to mitigate these problems. By raising native plants, they provide food for native bee pollinators like Lasioglossum vierecki and L. leucozonium, leading to less reliance on honey bee populations.
AS FOOD PRODUCERS
Honey is a natural product produced by bees and stored for their own use, but its sweetness has always appealed to humans. Before domestication of bees was even attempted, humans were raiding their nests for their honey. Smoke was often used to subdue the bees and such activities are depicted in rock paintings in Spain dated to 15,000 BC.
Honey bees are used commercially to produce honey. They also produce some substances used as dietary supplements with possible health benefits, pollen, propolis, and royal jelly, though all of these can also cause allergic reactions.
AS FOOD (BE BROOD)
Bees are partly considered edible insects. Indigenous people in many countries eat insects, including the larvae and pupae of bees, mostly stingless species. They also gather larvae, pupae and surrounding cells, known as bee brood, for consumption. In the Indonesian dish botok tawon from Central and East Java, bee larvae are eaten as a companion to rice, after being mixed with shredded coconut, wrapped in banana leaves, and steamed.
Bee brood (pupae and larvae) although low in calcium, has been found to be high in protein and carbohydrate, and a useful source of phosphorus, magnesium, potassium, and trace minerals iron, zinc, copper, and selenium. In addition, while bee brood was high in fat, it contained no fat soluble vitamins (such as A, D, and E) but it was a good source of most of the water-soluble B-vitamins including choline as well as vitamin C. The fat was composed mostly of saturated and monounsaturated fatty acids with 2.0% being polyunsaturated fatty acids.
AS ALTERNATIVE MEDICINE
Apitherapy is a branch of alternative medicine that uses honey bee products, including raw honey, royal jelly, pollen, propolis, beeswax and apitoxin (Bee venom). The claim that apitherapy treats cancer, which some proponents of apitherapy make, remains unsupported by evidence-based medicine.
STINGS
The painful stings of bees are mostly associated with the poison gland and the Dufour's gland which are abdominal exocrine glands containing various chemicals. In Lasioglossum leucozonium, the Dufour's Gland mostly contains octadecanolide as well as some eicosanolide. There is also evidence of n-triscosane, n-heptacosane, and 22-docosanolide. However, the secretions of these glands could also be used for nest construction.
WIKIPEDIA
Baer's pochard (Aythya baeri) is a diving duck found in eastern Asia. It is a resident bird in North and Central China, formerly bred in southeast Russia and Northeast China, migrating in winter to southern China, Vietnam, Japan, and India. Baer's pochard is a monotypic species. The holotype was collected in middle Amur.
It has a distinctive black head and neck with green gloss not present elsewhere in Aythya. While in poor light, it is likely to look completely black. It is very similar and closely related to the ferruginous duck, and they were previously considered to be a single species; Baer's pochard is differentiated by its white flanks when floating on the water, as well as its larger size and longer, more rounded head.
Its breeding season varies by latitude and environment. The nest, built from sedges, reeds and other plants, is placed among emergent vegetation, usually in shallow water or on small islands or ridges. Its clutch size ranges from 5 to 14. Males usually take on sentry duty, and females take on the responsibility of incubating.
Baer's pochard was once a common species in its range, but is now very rare. The number of mature individuals may be less than 1,000, and its population is still declining. Hunting and habitat loss are considered to be the main reasons. This species has been classified as critically endangered by the IUCN, and listed as a first-class protected animal in China.
Taxonomy
Baer's pochard was first scientifically described in 1863 as Anas baeri by Gustav Radde in his book Reisen im Süden von Ost-Sibirien. The epithet and English common name commemorate the Baltic German naturalist Karl Ernst von Baer. It is also called eastern white-eye, Siberian white-eye, Baer's white-eye and green-headed pochard. The holotype was collected from a small flock in middle Amur during the breeding season. In 1929, when British ornithologist E. C. Stuart Baker studied the birds of British India, he treated Baer's pochard and ferruginous duck as conspecific. However, Chinese ornithologist Tso-hsin Cheng treated them as two distinct species, as they had breeding grounds which did not overlap, and he had seen no evidence of hybridisation. While the species was long thought to have arisen from eastern populations of the ferruginous duck, American ornithologist Paul Johnsgard says its behaviors suggest it may instead be more closely related to the hardhead.
American ornithologist Bradley Curtis Livezey published a phylogenetic study based on morphological data in 1996, in which he proposed his view on the relationship among Tribe Aythyini. Baer's pochard, ferruginous duck, hardhead and Madagascar pochard are classified in subgenus Nyroca (the "white-eyes"), intrasubgenus relationship is unclear, but the ferruginous duck was suggested to be the sister group of Baer's pochard. The subgenus Aythya (the "scapu", including New Zealand Scaup, ring-necked duck, tufted duck, greater scaup and lesser scaup) is the sister group of subgenus Nyroca. The subgenus Aristonetta (the "redheads", including the common pochard, canvasback and redhead) is the sister group of all other pochards.
Two molecular phylogenetic studies on Anseriformes or Anatidae were published in 2000s, some mitochondrial genes were sequenced, but Baer's pochard was absent in both of them. The mitochondrial genome of Baer's pochard was sequenced and published in 2021. Molecular phylogenetic studies determined the relationships among Baer's pochard and other closely related species:
Tribe. Aythyini
Aythya
Baer's pochard Aythya baeri
Tufted Duck A. fuligula
Common pochard A. ferina
Redhead A. americana
Netta
Red-crested pochard Netta rufina
Asarcornis
White-winged duck Asarcornis scutulata
Description
The Baer's pochard is 41–47 cm (16–19 in) long with a 70–79 cm (28–31 in) wingspan. The male is slightly larger, weighing on average 500–730 g (18–26 oz), wings lengthed 18.6–20.3 cm (7.3–8.0 in), tail at 53–60 mm (2.1–2.4 in), and culmen at 38–44 mm (1.5–1.7 in). Relatively, the female weighing on average 590–655 g (20.8–23.1 oz), wings lengthed 19.1–20.5 cm (7.5–8.1 in), tail at 51–64 mm (2.0–2.5 in), and culmen at 40–44 mm (1.6–1.7 in). Both male and female's tarsometatarsus lengthed 33–34.7 mm (1.30–1.37 in).
Breeding male has a black head and neck with green gloss, white or paler yellow eyes, blackish-brown back, dark chestnut breast, white or light chestnut flanks and a short and low tail. The green gloss on its head is unique among Aythya. While it is likely to look completely black in poor light. Female has a dark brown head and neck that blend into the chestnut-brown breast and flanks. Eclipse and first-winter male resembles female, but retain the white eyes, while female has brown eyes. Both male and female have wide white speculum feathers, white vent-side, dark-grey bill, black nail and dark-grey tarsometatarsus.
It is similar to its close relative, the ferruginous duck (A. nyroca), both have white vent-side and iris in males, black nail, and wide white speculum feathers. Although Baer's pochard is bigger, has a longer head, body and bill. Unlike the ferruginous duck's tall and triangular head, Baer's pochard has a more rounded head and a flatter forehead. The white part on the belly extends to its flanks in Baer's pochard, which is visible when floating on the water, while the ferruginous duck has a smaller white part on its belly. The female Baer's pochard has a distinctly bright chestnut spot at the lore, which is absent in ferruginous duck.
Baer's pochard is usually a quieter duck, but during its courtship display, both sexes give harsh graaaak. Females may give kura kura kura and males may give kuro kuro at other times.
Distribution
Baer's pochard traditionally bred in the Amur and Ussuri basins in Northeast China and the southeastern Russian Far East. In recent years, it has also colonised North China and Central China. It winters in most areas south of the Yellow River in China, Taiwan, Japan, Bangladesh, India, North Korea, Laos, Myanmar, Nepal, Thailand and Vietnam, and occasionally appears in Bhutan, South Korea, Philippines or Pakistan as a rare vagrant. It leaves its wintering grounds by mid-March and returns to them by mid-October or early November.
The species has become extremely rare in its traditional breeding areas, and since 2010, there have been no confirmed breeding reports in all sites north of Beijing. However, the numbers recorded during the breeding season are smaller than those recorded in winter, so there may still be unknown breeding sites. For example, there are some doubtful breeding reports in the Chinese part of Lake Khanka, the Russian part of Lake Khasan, and the Muraviovka Park [ru]. Since 2012, new breeding sites have been discovered in several provinces of China, including Hebei, Hubei and Jiangxi; the latter two cities are far from traditional breeding sites in the Amur and Ussuri basins.[1] In these new breeding areas, warmer climate conditions provide a longer breeding season (about twice as long as in the Amur and Ussuri basins) which allows birds to lay a replacement clutch if their first clutch fails. Baer's pochard is no longer migratory in central and eastern China.
The wintering grounds have also contracted significantly in recent years. Since at least the winter of 2010-2011, Baer's pochard no longer winters in any site outside mainland China, except as a vagrant. In its wintering grounds in mainland China, the population has also declined severely, by more than 99%.
Behaviour and ecology
Baer's pochard is a shy species, that inhabit open, slow-flowing lakes, swamps and ponds. It breeds around lakes with rich aquatic vegetation, nesting in dense grass, flooded tussock meadows, or flooded shrubby meadows. In winter, it forms large flocks on large and open freshwater lakes and reservoirs with other pochards. It has strong wings, and can flyor walk at high speeds. It is also good at diving and swimming, and can quickly take off from the water when threatened or disturbed. In migrating season, they form small groups of more than 10 or dozens of birds, flying at low altitudes in wedge-shaped formations. During winter, Baer's pochard sleeps during the day, leaves for unknown feeding sites with other ducks in the dusk, and returns before dawn. Little is known about their diet beyond aquatic plants, grass seeds and molluscs.
Breeding
Baer's pochard appears to have a monogamous mating system, at least within a breeding season. In traditional breeding grounds in northeastern China, Baer's pochard gathers in gaps in the ice before it completely thawed. After the ice season, it gathers on the large, open lakes. They breed from mid-to-late May. While in Fuhe Wetland in Wuhan, Hubei, Baer's pochard gathers in large groups on the open lakes before breeding season. It is divided into small groups in mid-April, in which they will courting and mating. During courtship, the male swims around the female, repeatedly nods his head up and down. When other males approach, it swims toward them quickly to drive them away, but there is no violent fight between them. The female also nods her head in response. When the male approaches, the female straightens her neck and lowers her head to the water. He then climbs onto her body and bites her nape feathers to mate. After the mating, the male and female leave the flock for nesting.
Baer's pochard's nest is circular cylindrical, located among emergent vegetation, usually in shallow water or on small islands or ridges. The nest is made of sedges, reeds and other plants collected from the immediate vicinity, lined with a layer of down. Its clutch ranged from 5 to 14, with an average of 9.7. Males usually take on sentry duty at about 10 meters from the nest during hatching. Females leave the nest to forage 2–3 times a day, usually during 6:00-20:00, and lasted for 27–240 min. They cover the eggs with nest materials during forging, and place them onto their back when coming back. If water levels are elevated by heavy rainfall or human activity, females increase the height of the nest to avoid flooding. During the hottest days, females often stand on the nest and shelter eggs from the strong sunlight, whilst allowing circulation of air around them. Females also take water into their plumage and use it to cool the eggs. The incubation lasted for 23-26 days.
Studies have shown that the nest survival rate[note 3] of Baer's pochards is about 14–45%, and each clutch may lose one to nine eggs. About 20-30% of eggs hatched successfully, and 3–16 young fledged per nest. There are three major reasons contributing to the failure, including nest desertion (abandoned by parents), nest predation (mainly by Siberian Weasels) and flooding. The proportion of these causes varies among years. In addition, most of the breeding sites in Wuhan are Crayfish farms, the farming work and eggs collection may also be hindrances.
Biological interaction
Incomplete inter- and intra-specific brood parasitism were found in Baer's pochard. In Xianghai National Nature Reserve [zh], Baer's pochards could parasitize gadwall and common pochard, and may be parasitized by common pochard. In Wuhan, Baer's pochard shares breeding sites with cotton teal, eastern spot-billed duck and mallard. Interspecific brood parasitism was not observed. Intraspecific parasitic was found in Wuhan. If caught, the parasite will get attacked by the host.
Baer's pochard has hybridized with lesser scaup, common pochard, ferruginous duck, New Zealand scaup, chestnut teal and wood duck in captivity. Ferruginous duck was observed displaying to Baer's pochards several times in China and South Korea. Some individuals showed mixed characteristics of common, ferruginous and Baer's pochards, so they may be currently hybridising in the wild. The Baer's pochard has declined sharply in recent years, but the ferruginous and common pochard has expanded their breeding grounds, and even to the core areas of Baer's pochard's, which makes the hypothesis possible.
The research on its gut microbiota showed that the richest microorganism phyla of Baer's pochard are Bacillota, Pseudomonadota and Bacteroidota, which were consistent with those of the domestic goose, duck and chicken. The gut microbiota in diarrheic Baer's pochard is low in diversity, and the species were also significantly different from healthy individuals. Most species in reduced numbers are thought to be intestinal beneficial bacteria.
Threats and protection
Baer's pochard was once a common species in its range, but is now very rare. Mature individuals may be less than 1,000. According to records in China, there were 16,792 wintering individuals from 1986/87 to 1992/93, but only 3,472 from 1993/94 to 1998/99, and only 2,131 from 2002/03 to 2010/11. Bangladesh had more than 3,000 in 1996, India had more than 1,400 in 1995 and 1997, Myanmar had about 500-1,000 in the 1990s, and 596 were counted in 1998 in Thailand. While by 1999/00-2004/05, only 719 were counted in all wintering grounds except China, and only 48 individuals in 2005/06-2010/11. In China, hunting and habitat loss were considered to be the main threats. From 336 to 4,803 pochards were hunted annually in Honghu, Hubei from 1981 to 1997; in areas near Rudong County, maybe 3,000 are hunted every year. The wintering grounds have been significantly changed due to water pollution, fishing management, changes in aquatic plants, and the changing ecology of many wetlands in the Yangtze River floodplain. Factors in breeding and migrating grounds may also have contributed to its decline. The global decline shows no sign of slowing or stopping.
Baer's pochard was formerly classified as a vulnerable species by the IUCN. Recent research has shown that its numbers are decreasing more and more rapidly, and it was consequently uplisted to endangered status in 2008. In 2012, it was further uplisted to critically endangered. In 2014, the East Asian–Australasian Flyway Partnership (EAAFP) drafted the Baer's Pochard Task Force and it was endorsed in Jan 2015. Baer's pochard was listed as a first-class protected animal in China by 2021. In 2022, media reports state that the first captive population in China was established in the Beijing Zoo, with totally 54 individuals. It is planned to be further expanded and used for reintroduction.
A study published in 2022 showed that most breeding sites (81.8%) and suitable habitats (94%) are not located in protected areas, and overlap with large cities. Current protected areas may be less effective for the conservation under predicted global climate change, closely coordinated cross-border cooperation would be critical for Baer's pochard
Baer's pochard (Aythya baeri) is a diving duck found in eastern Asia. It is a resident bird in North and Central China, formerly bred in southeast Russia and Northeast China, migrating in winter to southern China, Vietnam, Japan, and India. Baer's pochard is a monotypic species. The holotype was collected in middle Amur.
It has a distinctive black head and neck with green gloss not present elsewhere in Aythya. While in poor light, it is likely to look completely black. It is very similar and closely related to the ferruginous duck, and they were previously considered to be a single species; Baer's pochard is differentiated by its white flanks when floating on the water, as well as its larger size and longer, more rounded head.
Its breeding season varies by latitude and environment. The nest, built from sedges, reeds and other plants, is placed among emergent vegetation, usually in shallow water or on small islands or ridges. Its clutch size ranges from 5 to 14. Males usually take on sentry duty, and females take on the responsibility of incubating.
Baer's pochard was once a common species in its range, but is now very rare. The number of mature individuals may be less than 1,000, and its population is still declining. Hunting and habitat loss are considered to be the main reasons. This species has been classified as critically endangered by the IUCN, and listed as a first-class protected animal in China.
Taxonomy
Baer's pochard was first scientifically described in 1863 as Anas baeri by Gustav Radde in his book Reisen im Süden von Ost-Sibirien. The epithet and English common name commemorate the Baltic German naturalist Karl Ernst von Baer. It is also called eastern white-eye, Siberian white-eye, Baer's white-eye and green-headed pochard. The holotype was collected from a small flock in middle Amur during the breeding season. In 1929, when British ornithologist E. C. Stuart Baker studied the birds of British India, he treated Baer's pochard and ferruginous duck as conspecific. However, Chinese ornithologist Tso-hsin Cheng treated them as two distinct species, as they had breeding grounds which did not overlap, and he had seen no evidence of hybridisation. While the species was long thought to have arisen from eastern populations of the ferruginous duck, American ornithologist Paul Johnsgard says its behaviors suggest it may instead be more closely related to the hardhead.
American ornithologist Bradley Curtis Livezey published a phylogenetic study based on morphological data in 1996, in which he proposed his view on the relationship among Tribe Aythyini. Baer's pochard, ferruginous duck, hardhead and Madagascar pochard are classified in subgenus Nyroca (the "white-eyes"), intrasubgenus relationship is unclear, but the ferruginous duck was suggested to be the sister group of Baer's pochard. The subgenus Aythya (the "scapu", including New Zealand Scaup, ring-necked duck, tufted duck, greater scaup and lesser scaup) is the sister group of subgenus Nyroca. The subgenus Aristonetta (the "redheads", including the common pochard, canvasback and redhead) is the sister group of all other pochards.
Two molecular phylogenetic studies on Anseriformes or Anatidae were published in 2000s, some mitochondrial genes were sequenced, but Baer's pochard was absent in both of them. The mitochondrial genome of Baer's pochard was sequenced and published in 2021. Molecular phylogenetic studies determined the relationships among Baer's pochard and other closely related species:
Tribe. Aythyini
Aythya
Baer's pochard Aythya baeri
Tufted Duck A. fuligula
Common pochard A. ferina
Redhead A. americana
Netta
Red-crested pochard Netta rufina
Asarcornis
White-winged duck Asarcornis scutulata
Description
The Baer's pochard is 41–47 cm (16–19 in) long with a 70–79 cm (28–31 in) wingspan. The male is slightly larger, weighing on average 500–730 g (18–26 oz), wings lengthed 18.6–20.3 cm (7.3–8.0 in), tail at 53–60 mm (2.1–2.4 in), and culmen at 38–44 mm (1.5–1.7 in). Relatively, the female weighing on average 590–655 g (20.8–23.1 oz), wings lengthed 19.1–20.5 cm (7.5–8.1 in), tail at 51–64 mm (2.0–2.5 in), and culmen at 40–44 mm (1.6–1.7 in). Both male and female's tarsometatarsus lengthed 33–34.7 mm (1.30–1.37 in).
Breeding male has a black head and neck with green gloss, white or paler yellow eyes, blackish-brown back, dark chestnut breast, white or light chestnut flanks and a short and low tail. The green gloss on its head is unique among Aythya. While it is likely to look completely black in poor light. Female has a dark brown head and neck that blend into the chestnut-brown breast and flanks. Eclipse and first-winter male resembles female, but retain the white eyes, while female has brown eyes. Both male and female have wide white speculum feathers, white vent-side, dark-grey bill, black nail and dark-grey tarsometatarsus.
It is similar to its close relative, the ferruginous duck (A. nyroca), both have white vent-side and iris in males, black nail, and wide white speculum feathers. Although Baer's pochard is bigger, has a longer head, body and bill. Unlike the ferruginous duck's tall and triangular head, Baer's pochard has a more rounded head and a flatter forehead. The white part on the belly extends to its flanks in Baer's pochard, which is visible when floating on the water, while the ferruginous duck has a smaller white part on its belly. The female Baer's pochard has a distinctly bright chestnut spot at the lore, which is absent in ferruginous duck.
Baer's pochard is usually a quieter duck, but during its courtship display, both sexes give harsh graaaak. Females may give kura kura kura and males may give kuro kuro at other times.
Distribution
Baer's pochard traditionally bred in the Amur and Ussuri basins in Northeast China and the southeastern Russian Far East. In recent years, it has also colonised North China and Central China. It winters in most areas south of the Yellow River in China, Taiwan, Japan, Bangladesh, India, North Korea, Laos, Myanmar, Nepal, Thailand and Vietnam, and occasionally appears in Bhutan, South Korea, Philippines or Pakistan as a rare vagrant. It leaves its wintering grounds by mid-March and returns to them by mid-October or early November.
The species has become extremely rare in its traditional breeding areas, and since 2010, there have been no confirmed breeding reports in all sites north of Beijing. However, the numbers recorded during the breeding season are smaller than those recorded in winter, so there may still be unknown breeding sites. For example, there are some doubtful breeding reports in the Chinese part of Lake Khanka, the Russian part of Lake Khasan, and the Muraviovka Park [ru]. Since 2012, new breeding sites have been discovered in several provinces of China, including Hebei, Hubei and Jiangxi; the latter two cities are far from traditional breeding sites in the Amur and Ussuri basins.[1] In these new breeding areas, warmer climate conditions provide a longer breeding season (about twice as long as in the Amur and Ussuri basins) which allows birds to lay a replacement clutch if their first clutch fails. Baer's pochard is no longer migratory in central and eastern China.
The wintering grounds have also contracted significantly in recent years. Since at least the winter of 2010-2011, Baer's pochard no longer winters in any site outside mainland China, except as a vagrant. In its wintering grounds in mainland China, the population has also declined severely, by more than 99%.
Behaviour and ecology
Baer's pochard is a shy species, that inhabit open, slow-flowing lakes, swamps and ponds. It breeds around lakes with rich aquatic vegetation, nesting in dense grass, flooded tussock meadows, or flooded shrubby meadows. In winter, it forms large flocks on large and open freshwater lakes and reservoirs with other pochards. It has strong wings, and can flyor walk at high speeds. It is also good at diving and swimming, and can quickly take off from the water when threatened or disturbed. In migrating season, they form small groups of more than 10 or dozens of birds, flying at low altitudes in wedge-shaped formations. During winter, Baer's pochard sleeps during the day, leaves for unknown feeding sites with other ducks in the dusk, and returns before dawn. Little is known about their diet beyond aquatic plants, grass seeds and molluscs.
Breeding
Baer's pochard appears to have a monogamous mating system, at least within a breeding season. In traditional breeding grounds in northeastern China, Baer's pochard gathers in gaps in the ice before it completely thawed. After the ice season, it gathers on the large, open lakes. They breed from mid-to-late May. While in Fuhe Wetland in Wuhan, Hubei, Baer's pochard gathers in large groups on the open lakes before breeding season. It is divided into small groups in mid-April, in which they will courting and mating. During courtship, the male swims around the female, repeatedly nods his head up and down. When other males approach, it swims toward them quickly to drive them away, but there is no violent fight between them. The female also nods her head in response. When the male approaches, the female straightens her neck and lowers her head to the water. He then climbs onto her body and bites her nape feathers to mate. After the mating, the male and female leave the flock for nesting.
Baer's pochard's nest is circular cylindrical, located among emergent vegetation, usually in shallow water or on small islands or ridges. The nest is made of sedges, reeds and other plants collected from the immediate vicinity, lined with a layer of down. Its clutch ranged from 5 to 14, with an average of 9.7. Males usually take on sentry duty at about 10 meters from the nest during hatching. Females leave the nest to forage 2–3 times a day, usually during 6:00-20:00, and lasted for 27–240 min. They cover the eggs with nest materials during forging, and place them onto their back when coming back. If water levels are elevated by heavy rainfall or human activity, females increase the height of the nest to avoid flooding. During the hottest days, females often stand on the nest and shelter eggs from the strong sunlight, whilst allowing circulation of air around them. Females also take water into their plumage and use it to cool the eggs. The incubation lasted for 23-26 days.
Studies have shown that the nest survival rate[note 3] of Baer's pochards is about 14–45%, and each clutch may lose one to nine eggs. About 20-30% of eggs hatched successfully, and 3–16 young fledged per nest. There are three major reasons contributing to the failure, including nest desertion (abandoned by parents), nest predation (mainly by Siberian Weasels) and flooding. The proportion of these causes varies among years. In addition, most of the breeding sites in Wuhan are Crayfish farms, the farming work and eggs collection may also be hindrances.
Biological interaction
Incomplete inter- and intra-specific brood parasitism were found in Baer's pochard. In Xianghai National Nature Reserve [zh], Baer's pochards could parasitize gadwall and common pochard, and may be parasitized by common pochard. In Wuhan, Baer's pochard shares breeding sites with cotton teal, eastern spot-billed duck and mallard. Interspecific brood parasitism was not observed. Intraspecific parasitic was found in Wuhan. If caught, the parasite will get attacked by the host.
Baer's pochard has hybridized with lesser scaup, common pochard, ferruginous duck, New Zealand scaup, chestnut teal and wood duck in captivity. Ferruginous duck was observed displaying to Baer's pochards several times in China and South Korea. Some individuals showed mixed characteristics of common, ferruginous and Baer's pochards, so they may be currently hybridising in the wild. The Baer's pochard has declined sharply in recent years, but the ferruginous and common pochard has expanded their breeding grounds, and even to the core areas of Baer's pochard's, which makes the hypothesis possible.
The research on its gut microbiota showed that the richest microorganism phyla of Baer's pochard are Bacillota, Pseudomonadota and Bacteroidota, which were consistent with those of the domestic goose, duck and chicken. The gut microbiota in diarrheic Baer's pochard is low in diversity, and the species were also significantly different from healthy individuals. Most species in reduced numbers are thought to be intestinal beneficial bacteria.
Threats and protection
Baer's pochard was once a common species in its range, but is now very rare. Mature individuals may be less than 1,000. According to records in China, there were 16,792 wintering individuals from 1986/87 to 1992/93, but only 3,472 from 1993/94 to 1998/99, and only 2,131 from 2002/03 to 2010/11. Bangladesh had more than 3,000 in 1996, India had more than 1,400 in 1995 and 1997, Myanmar had about 500-1,000 in the 1990s, and 596 were counted in 1998 in Thailand. While by 1999/00-2004/05, only 719 were counted in all wintering grounds except China, and only 48 individuals in 2005/06-2010/11. In China, hunting and habitat loss were considered to be the main threats. From 336 to 4,803 pochards were hunted annually in Honghu, Hubei from 1981 to 1997; in areas near Rudong County, maybe 3,000 are hunted every year. The wintering grounds have been significantly changed due to water pollution, fishing management, changes in aquatic plants, and the changing ecology of many wetlands in the Yangtze River floodplain. Factors in breeding and migrating grounds may also have contributed to its decline. The global decline shows no sign of slowing or stopping.
Baer's pochard was formerly classified as a vulnerable species by the IUCN. Recent research has shown that its numbers are decreasing more and more rapidly, and it was consequently uplisted to endangered status in 2008. In 2012, it was further uplisted to critically endangered. In 2014, the East Asian–Australasian Flyway Partnership (EAAFP) drafted the Baer's Pochard Task Force and it was endorsed in Jan 2015. Baer's pochard was listed as a first-class protected animal in China by 2021. In 2022, media reports state that the first captive population in China was established in the Beijing Zoo, with totally 54 individuals. It is planned to be further expanded and used for reintroduction.
A study published in 2022 showed that most breeding sites (81.8%) and suitable habitats (94%) are not located in protected areas, and overlap with large cities. Current protected areas may be less effective for the conservation under predicted global climate change, closely coordinated cross-border cooperation would be critical for Baer's pochard
Otra ilustración a imagen y semejanza de las ilustraciones de ciencia ficción de los sesenta y setenta, sobre la exploración de la probióta intestinal. para DIANA
#arte #art #ilustración #illustration #probiota #intestino #car_t #DIANA #cienciaficcion #astronauta #astronaut
Leaf litter on the forest floor beneath plantings in Auwahi 2. Not that long ago this area was an extensive and exclusive blanket of kikuyu grass. Now the leaves, twigs, and lichen of the forest are once again combining to create this litter and new soil, and perhaps to rejuvenate the chemistry and microbiota that once existed here. (modified, of course, but introduced influences, such as the lack of any now-extinct species and the impacts of new species brought by the activities of humans)
Equally as important, as the soil accumulates the hydrology may return to what it once was, rather than being dominated by the grass and root system of kikuyu grass.
Begins With D
As of Jan. 1, food manufacturers, importers and retailers in the U.S. must comply with a new national labeling standard for food that's been genetically modified in a way that "isn't possible through natural growth."
Then it must be possible through UNNATURAL GROWTH, YIKES!
Make sure you read the labels on the back of the food packages you buy from the grocery store! The FDA no longer requires the "GMO" symbol on the "front" of packaging, now they hide it on the back of the package, not as a symbol but as the sentence "contains bioengineered food ingredient" that's very sneaky!
deohs.washington.edu/edge/blog/can-roundup-cause-cancer
Glyphosate (GMO) raised the risk of non-Hodgkin's lymphoma by 41%!!! In 2020 Monsanto paid over $10 billion to settle lawsuits involving the glyphosate-based herbicide Roundup. Glyphosate is GMO and Foods that are grown with glyphosate are bio-engineered & in my opinion, it's "not safe!" From what I've read it can affect gut microbiota.
This appears to be a giant crane fly (Tipula abdominalis). They feed on leaf litter, which is digested by their gut microbiota. Its presence is not surprising because we rake all of our autumn leaves into wooded parts of our yard, then I use multiple passes of our lawn mower to finely mulch the leaves. Faircrest neighborhood, Madison, Wisconsin, USA, May 26, 2025.
by Alanna Collen
Science writer with a Ph.D. in evolutionary biology takes the time to sum up the latest research on the micro biome in this story of the diseases of the 21st century.
She begins with the human genome project. It was going to be a huge deal and open up all kinds of possibilities for cures and designer babies. And then it didn’t as we don’t even have as many genes as a mouse. The same gene sequencing technology was then used to look at the DNA of our micro biome. These bacteria are the real key to our human health as well as the biggest impact on our evolution since the micro biome evolve so much faster than our own DNA. And we can hardly function without them. Bacteria process our food and produce by products we can use like serotonin and B12. They help us fight off disease, keep our single cell gut lining protected with mucus and perform a host of other services. They outnumber us 9 cells to our one, thus the title 10% human.
We come by our beneficial bacteria at birth gulping the fluids in the vagina along with a side of fecal matter with which to colonize our gut. Our parents skin bacteria colonize our own. The breast milk of our mother’s changes with each month of development to provide the right mix of nutrients plus bacteria that travels along the nipple.
The author investigates what we have done to disturb these helpful bacteria. How modern health practices including a huge increase in cesarean births and less breast feeding, hyper hygiene and an obsession with germ warfare along with the overuse of antibiotics has disturbed or wiped out important bacteria in our collaborative work with our micro biome. So here I found my answer to why we have so many new ridiculous diseases like peanut allergies. And the increase in autism may very well be a result of antibiotics reaping havoc in the bodies of infants at a crucial developmental stage making their brains do things in abnormal ways. And when this window of development closes the mind and body is stuck there. So many of our modern diseases seem to begin with a course of antibiotics.
Also included as a disease is obesity the abnormal enlargement of fat cells possibly caused by a virus or bacteria which also leads to inflammation. Some bacteria can harvest more energy from our food than others and push it into these storage cells no matter how little or how much we eat or exercise. The microbiota of obese people differ from those in lean people. In mice lean mice have been made fat by injecting them with the microbiota of fat ones and visa versa. Thus obesity could also be a disease we share with each other along with our microbes.
The science is still in its infancy as we are at the correlation stage and have not proved causation, but the implications are already writ large. The first chapter draws attention to the discovery that a virus may be causing obesity. While antibiotics can also make you fat. This is well known in animal agriculture as antibiotics have long been used to fatten up cattle. So here’s another thing we can stop blaming ourselves for and start searching for treatment in alternative medicine since Western medicine hasn’t anything to offer yet apart from diet and exercise. Oh wait. Some will do a fecal transplant. See below.
And speaking of diet we should feed the bacteria we collaborate with by making sure to eat enough fiber to make it to our colon. A reduction of real food in our diet especially fiber is a big contributor to lack of diversity in our gut bacteria leading to increase of modern diseases. Here I learned that there is actually a bacteria that only eats seaweed for us sushi lovers. And one that eats all the charred bits on your meat. The key to diversity is to eat lots of different foods, but especially plants, nuts and whole grains. The bacteria come into your body on these foods, but are kept alive by us feeding them more of the same.
A whole chapter is devoted to fecal transplants which I learned about in previous book on the micro biome. In these cases they were used to regenerate a healthy micro biome in humans with irritable bowel syndrome and other diseases of the digestive system usually triggered by a course of antibiotics. The author explores the possibility of people wanting to design their gut with such a transplant. This along with the chapter on how bacteria can alter behavior implies that many mental illnesses could benefit from such a procedure. Indeed if bacteria cause humans to behave in certain ways it makes one wonder how much of our personality is actually driven by our bacteria rather than by our own brain and identity. The author had her fecal sample analyzed at americangut.org/we-are-citizen-science/. Results mostly tell you how diverse you gut bacteria are.
I was also gratified to read how bath products interfere with the perfectly good cleansing system of the ammonia oxidizing bacteria on our skin. That a study has been done on indigenous people who have been undisturbed in their hygiene practice who don’t smell at all ever. Those who have been introduced to modern hygiene practices that they then practice haphazardly become perpetually stinky. A third group who do manage to adopt an optimum hygiene practice, as practiced by Westerners, don’t smell, but still stink after exerting themselves as do most Westerners.
The discovery of beneficial bacteria of the skin has prompted the formation of a company (motherdirt.com/) whose product promises to restore live bacteria to your skin. When I heard about this and read on the web the experiences of people who have given up body soap products altogether with no adverse affects I was prompted to do the same. Though hand washing is still adhered to for the usual safety reasons. Stripping the body of oils also makes you feel colder in cold climates as well as drying out your skin. Brushing my body with a body brush has become my substitute for soap and it feels great. I had eczema as a child and frighteningly dry skin which I coped with most of my life with various lotions and oils so I welcome the return of my own skin oils being left to their own self-cleaning devices. I’ve had no complaints that I smell though some more intimate with me have not liked the idea of my regime, feeling it is somehow unclean. Dogs love me though since I don’t stink of chemicals.
Americans have been germaphobes since our science became obsessed with germ theory. And this was a good thing in terms of the diseases that used to kill us for which we now have vaccines. But we took it too far and built an empire of products cluttering up the bathroom and kitchen. The discovery of the micro biome is very timely in our quest for a more sustainable lifestyle.
JURY DISTINCTION FOR CATEGORY 1. OBJECT OF STUDY
Entry in category 1. Object of study; Copyright CC-BY-NC-ND: Samuel Cia
Description:
These days, the brown marmorated stink bug, Halyomorpha halys, is a major invasive insect pest in European horticulture. By analysing the bug’s gut microbiota, we hope to find entomopathogenic bacteria which could be used as biological control agents. To this end, stink bugs had first to be caught and dissected. This image shows the dissected digestive tract of an adult H. halys, including fore-, mid- and hind guts as well as the insect’s red-coloured symbiont-inhabiting crypts. The gut dissection and image were made under a dissecting microscope. Neither the organs nor the image were artificially coloured.
Comment of the jury:
A beautiful and naturally coloured image of a very obscure field of research. While the jury liked the fragility and poetry the image conveys, this research into the gut microbiota of small bugs also points to an epistemological paradox: the careful study of entomopathogenic bacteria is being done primarily to find ways of controlling populations of the stink bug, which is considered a pest in horticulture.
A Gardener's Guide To The Soil Food Web
Elaine Ingham gives the intro to this book. She charges quite a bit of money to teach people how to make compost tea to boost the soil web for different purposes so I was curious.
The authors of this book have given a thorough description of the soil web much as I learned from other books about the microbiota. It is easy to understand and readable. The additional information I learned was that fruit trees like a fungus based nitrogen while vegetables like a bacteria based nitrogen. The fungus type is higher in acidity. This is important when making compost tea for one or the other. There is also a description of how nematodes can be friend or foe depending on who they are attacking.
The making of the compost tea is also covered. This is when I wanted to toss the book aside. The methodology here is far too much trouble and does not have a permaculture approach, but it does have its place for those profit oriented and commercial applications wanting to be organic.
My beloved microbes, why does everyone treat you like that? I wish I could inform the entire world that we cannot live without you or you without us...
Me loving them and others demonizing them because they are guided by their appearance or their smell and all the gossip involving them...
What would it be of us if they disappeared forever?
You are the beginning and the end, we are the enemy when we kill you mercilessly with bad habits, when we do not take care of our health in a timely manner...
I chose an E. coli because it is part of our microbiota but it can also be fatal. Every time that I show E. coli to someone with its bright green metallic color they are amazed by how beautiful and striking it is but when I tell them it’s a bacteria then they tell me it’s ugly. E. colo is also a type of bacteria that is most isolated in all types of cultures, every day it’s with me… inside of me so I have a special affection and respect for it.
Due to being Breast Cancer Awareness Month, I include the girl in a fighting position for the title of my agar and painted with my beautiful Escherichia coli.
Remember to take care of your general health just in case any vindictive E. coli attacks you…
Abstract
Space medicine research has drawn immense attention toward provision of efficient life support systems during long-term missions into space. However, in extended missions, a wide range of diseases may affect astronauts. In space medicine research, the gastrointestinal microbiome and its role in maintaining astronauts' health has received little attention.
We would like to draw researchers' attention to the significant role of microbiota. Because of the high number of microorganisms in the human body, man has been called a 'supra-organism' and gastrointestinal flora has been referred to as 'a virtual organ of the human body'.
In space, the lifestyle, sterility of spaceship and environmental stresses can result in alterations in intestinal microbiota, which can lead to an impaired immunity and predispose astronauts to illness. This concern is heightened by increase in virulence of pathogens in microgravity. Thus, design of a personal probiotic kit is recommended to improve the health status of astronauts.
Introduction
Living in space has been a great desire for mankind, leading to the development of space stations for long-duration manned space missions. The design of a life support system is needed to maintain the minimum life requirements for humans in space by conserving a stable body temperature, a standard pressure on the body and by managing waste products.
So far, the majority of research in this area has been devoted to the human primary requirements such as air, water and food. Furthermore, a life support system deals with astronauts' healthcare. Although health status of the astronauts such as immunological and physiological problems has been investigated, less attention has been paid to the intestinal microbiome and its significant role in the astronaut's health.
Immunological and physiological health problems could occur when considering the identified increase in the virulence and antibiotic resistance of some infectious bacteria exposed to microgravity, along with possible weakening of the immune system during space flight. Compensating for these alterations may not only enhance the health and immunity status of astronauts, but might have possible effects on enhancing the duration of space journeys.
For many years, the importance of intestinal flora in human health and disease has been known to man. Researchers have suggested a possible association between the changes in the balance of gut flora and several diseases. At the end of the Human Genome Project, the aggregation of flora genes within the human genome was named the 'human metagenome, highlighting the crucial role of the microbiome in the maintenance of health.
This perspective highlights the crucial role of the microbiome in the health and/or disease status in astronauts. Considering astronauts' special health and nutrition needs in orbit, it could be advantageous to develop probiotics for each crew member. These healthy bacteria could then be consumed during long-duration missions to replenish the intestinal microbiome.
The Human Intestine & the Microbiome
Today 'gut health' is a term increasingly used in the medical literature to describe effective digestion and absorption, the absence of gastrointestinal lesions, presence of normal intestinal microflora and proper immune function. However, from a scientific point of view, it is still extremely unclear what gut health is or how it can be defined and/or measured.
The interactions between the gastrointestinal barrier and the microbiome appear to be a complex mechanism that assists in maintaining gut health. The gastrointestinal tract contributes to digestion and absorption of nutrients, minerals and fluids, osmoregulation, endocrine regulation and host metabolism, mucosal and systemic tolerance, immunoenhancement, defense against potential pathogens and harmful substances, signaling from the periphery to the brain, and detoxification of toxic molecules originating from the environment or the host.
Recognition of the importance of gastrointestinal health and microflora can be an important asset to astronauts' health.
Across the large surface of the digestive tract, healthy and pathogenic bacteria compete for dominance. With such a huge exposure area, the immune system has a hard task of hindering pathogens from entering the blood and lymph. The presence of a balance between beneficial and potentially harmful bacteria is considered normal and contributes to a dynamic and healthy human gut.
One way to maintain this homeostasis is to introduce helpful bacteria or probiotics. After the first suggestion of the health benefits of probiotics in the early 20th century by Nobel Laureate Metchnikoff, many bacterial strains have been clinically tested as potential probiotics. Probiotics are thought to play a health-promoting role by improving intestinal microbial infections.
The surface area, apparent balance of microflora and health impact of the human gut reminds us that this complex organ must not be forgotten as one factor in long-duration spaceflight health.
Stress & Gut Microbiome
The Human Genome Project revealed that the human body is the habitat of microbial symbionts ten-times more in number than Homo sapiens cells. The recognition of the complex interactional environment between the human and our symbiotic microflora led researchers to name this the 'human microbiome'.
In the human gut, the microbiome directly influences biochemical, physiological and immunological pathways and is the first line of resistance to various diseases.
Traveling can act as an environmental stress causing changes in the microbiome composition or its gene expression. This may lead to the transient (as in travelers' diarrhea) or permanent dominance of pathogenic gut bacteria. Recently, it was shown that exposure to a social stressor altered the composition of the intestinal microbiome, indicating stressor-induced immunomodulation.
It was demonstrated that stressor exposure changes the stability of the microflora and leads to bacterial translocation. Circulating levels of IL-6 and MCP-1 increased with stressor exposure and these increases were significantly and positively correlated to changes in three bacterial genera (i.e., Coprococcus, Pseudobutyrivibrio and Dorea) in the cecum.
This suggested that the microbiome somehow contributed to stressor-induced immunoenhancement. To test the theory, in follow-up experiments, mice were treated with an antibiotic cocktail to determine whether reducing microflora would annul this stressor-induced increase in circulating cytokines.
In the antibiotic-treated mice, exposure to the same stressor failed to increase IL-6 and MCP-1 confirming that intestinal microflora were necessary for the observed increase in circulating cytokines.
Microgravity Stress Alters Bacterial Virulence
Studies have shown an increase in the virulence, changes in growth modulation and alterations in response to antibiotics in certain bacteria both in space and simulated microgravity. Significant technological and logistical hurdles have hindered thorough genotypic and phenotypic analyses of bacterial response to actual space environment.
In this line, Wilson et al. cultured Salmonella enterica Typhimurium aboard space shuttle mission STS-115 with identical cultures as ground controls. Global microarray and proteomic analyses were carried out and 167 differentially expressed transcripts and 73 proteins were identified among which conserved RNA-binding protein Hfq was suggested as a likely global regulator involved in the response to spaceflight.
Similar results were obtained with ground-based microgravity culture model. Furthermore, spaceflight-grown S. enterica Typhimurium had enhanced virulence in murine models and exhibited extracellular matrix accumulation consistent with a biofilm. Typhimurium grown in spaceflight analog exhibited increased virulence, increased resistance to environmental stresses (acid, osmotic and thermal stress), increased survival in macrophages and global changes in gene expression.
Low-shear modeled microgravity rendered adherent–invasive Escherichia coli more adherent to a mammalian gastrointestinal epithelial-like cell line, Caco-2. Simulated microgravity conditions markedly increased production of the heat-labile enterotoxin from enterotoxigenic E. coli. Upon a 12-day exposure to low-shear modeled microgravity, Candida albicans exhibited increased filamentation, formation of biofilm communities, phenotypic switching and more resistance to the antifungal agent amphotericin B.
Only one virulence gene was found among 163 differentially expressed genes in simulated microgravity grown S. Typhimurium and actually, most virulence genes were expressed at a lower level (including genes involved in lipopolysaccharide production). Furthermore, sigma factor (a transcription factor responsible for a general stress response) was not thought to be a cause, since a decreased level of its gene expression was observed in simulated microgravity.
The mechanism of enhanced virulence of S. Typhimurium grown in actual spaceflight and rotating wall vessel culture conditions does not involve an increased expression of traditional genes that regulate the virulence of this bacterium under normal gravity conditions; however, Hfq pathway is required for full virulence in S. Typhimurium.
Biofilm formation is part of the normal growth cycle of most bacteria and this film is linked to chronic diseases that are difficult to treat such as endocarditis, cystitis and bacterial otitis media. Bacterial biofilm creates superior resistance to oxidative, osmolarity, pH and antibiotic stresses.
Theoretically, bacterial biofilm production, which enhances bacterial survival by resistance to the immune system and antimicrobial agents, may increase the risk and/or severity of infection in long-term space missions. Diminished gravity has been shown to stimulate bacterial biofilm formation both in E. coli and Pseudomonas aeruginosa. In a study by Crabbe et al. in 2008, rotating wall vessel technology was exploited to study the effect of microgravity on growth behavior of P. aeruginosa PAO1.
Rotating wall vessel cultivation resulted in a self-aggregating phenotype, which subsequently led to formation of biofilms. In a second study in 2010, the same researchers employed microarrays to investigate the response of P. aeruginosa PAO1 to low-shear modeled microgravity both in rotating wall vessel and random position machine.
P. aeruginosa demonstrated increased alginate production and upregulation of AlgU-controlled transcripts (including those coding for stress-related proteins) in modeled microgravity. Results of the study also implicated the involvement of Hfq in response of P. aeruginosa to simulated microgravity. Involvement of Hfq in response of P. aeruginosa to actual spaceflight was later confirmed in another study.
In addition, there is concern that antibiotic-resistance increases during short-term spaceflight. The MIC of both colistin and kanamycin increased significantly in E. coli grown aboard the flight module compared with the MIC on the ground. A similar increase in the MIC of oxacillin, erythromycin and chloramphenicol was reported in Staphylococcus aureus. This has led to concerns that the efficacy of antibiotics may be diminished during even short orbital missions.
It has been hypothesized that reduction in the natural, terrestrial diversity of the gastrointestinal bacterial microflora in spaceflight may give rise to an increase in the presence of the drug-resistant bacteria. It has also been postulated that the emergence of such resistant clones could be facilitated by the administration of antibiotics either before or during the flight.
Emergence of drug resistance is also facilitated by bacterial mutation which occurs more frequently in long-term spaceflights. Overall, there is the possibility that drug-resistant bacteria could colonize all crew members on a mission, giving rise to a difficult-to-treat healthcare problem.
Spaceflight & the Microbiome
In an attempt to protect astronauts from exposure to novel pathogens preflight, several guidelines are carried out. Prelaunch, crew members are limited both in travel and visitors to limit pathogen exposure. Therefore, crew members tend to launch with normal gut microflora and with a reduced risk of gut infection.
Items flown to the International Space Station (ISS) are cleaned before loading to limit introducing bacteria to the environment. Once in orbit, all areas in the ISS have ultra-high-efficiency bacterial filters in the air supply ducts to reduce the levels of bacteria and fungi. Finally, cleaning of the surfaces of the modules is a regular 'housekeeping' chore to limit bacterial and fungal growth.
Still, microorganisms exist on the ISS. No matter how much cleaning is done, microorganisms are continuously shed from skin, mucous membranes, gastrointestinal and respiratory tracts or can be released by sneezing, coughing and talking. Specimens were obtained for mycological examination from the skin, throat, urine and feces of the six astronauts who conducted the Apollo 14 and Apollo 15 lunar exploration missions both before and after flight.
Analysis of preflight data demonstrated that the process of severely restricting opportunities for colonization for 3 weeks before flight resulted in a 50% reduction in the number of isolated species. Postflight data indicated that exposure to the spaceflight environment for up to 2 weeks resulted in an even greater reduction with a relative increase in the potential pathogen C. albicans.
The compositions of intestinal, oral and nasal flora have been shown to change even during short spaceflights. In one study, a reduction in the number of nonpathogenic bacteria and an increase in the number of opportunistic pathogens has been reported in the nasal flora of cosmonauts. A significant reduction in the number of bacterial species of the intestine has been seen after 2 weeks of spaceflight.
These observations were similar to changes seen in ground volunteers who were kept in isolation, in which volunteers were fed only sterilized, dehydrated foods. A significant decrease in the number of bifidobacteria, lactobacilli and other bacteria was seen. In a Russian experiment, a decrease in lactobacilli (and replacement with pathogens) were seen in mouth and throat cavities in all mission members in in-flight period.
Spaceflights and even the preparation phase before take-off can exert dysbiosis in the human microflora which results in reduction of the defense group of microorganisms (bifidobacteria and lactobacilli) and appearance of opportunistic pathogens such as E. coli, enterobacteria and clostridia. Subsequently, this procedure can lead to accumulation of the potentially pathogenic species and their long-term persistence.
Colonization resistance is one of the factors that needs to be taken into account to stabilize the microflora of the cosmonauts during space flights. Indigenous microflora are vital for preservation of microecological homeostasis. It has been hypothesized that a regular intake of probiotic foods might be helpful in correcting this change.
Human microflora functions as a barrier against antigens from microorganisms and food. Alterations in the microbiome composition have been reported in inflammatory bowel disease, inflammatory conditions, ulcerative colitis and more. Healthy immunophysiologic regulation in the gut has been hypothesized to depend on the establishment of indigenous microflora that create specific immune responses at the gut and system levels.
Furthermore, gut microflora has a role in induction and maintenance of oral tolerance in experimental animal models. Changes in the diversity and number of gut microflora have been linked to a deficient immune system as well as immunological dysregulation which is associated with many human noninfectious diseases such as autoimmunity, allergy and cancer.
Reinforcing this concept of health symbiosis, studies of germ-free animal showed wide-ranging defects in the development and maturation of gut-associated lymphoid tissues. Another way of viewing this health interaction comes from the data that ten Salmonella bacteria have been shown to induce infection in germ-free mice, while 109 bacteria are needed to induce infection in a conventional animal possessing intact intestinal microflora.
To maintain astronaut health on orbit, an awareness of the importance of a balanced gut microbiome to maintaining the immune homeostasis and resistance to infections is valuable.
Previous studies have shown that important immune parameters are decreased during spaceflight. Reductions in the number and proportion of lymphocytes and their cytokine production, depression of dendritic cells function and T-cell activation, and finally reduction in numbers of monocytes and precursors of macrophages, have been noted.
In one study, stresses associated with spaceflight were shown to alter important functions of neutrophils and monocytes. In another study, the astronauts' monocyte functions showed reductions in their ability to engulf E. coli, elicit an oxidative burst and degranulation. Non-MHC-restricted (CD56) killer cell cytotoxicity tends to decrease after short-term spaceflight.
In the latter study, the authors examined the age, gender (nine men and one woman), flight experience, mission factors and mission role (e.g., pilot, scientist or crew) of the astronauts and found no correlation between these variables and individual non-MHC killer cell function levels.
Therefore, other factors may contribute to the compromised immune system in space. Decreased natural killer cell cytotoxicity in cosmonauts after short- and long-term spaceflights have also been reported. Reductions in absolute numbers of lymphocytes, eosinophils and natural killer cells, reduced lymphocyte mitogenic response, diminished delayed-type hypersensitivity, changes in CD4+:CD8+ ratios and reduced production of IL-2 and IFN-γ have also been reported.
The immune system changes of astronauts as well as environmental stress may have been a factor in known incidents of infectious illness in crew members. During the Apollo 8 preflight period for instance, all crew members suffered viral gastroenteritis. During flight, the effects of mission duration on the neuroimmune responses in astronauts were studied and changes in plasma cortisol, epinephrine, norepinephrine, total IgE levels, number of white blood cells, polymorphonuclear leukocytes and CD4+ T cells were found at different times.
Upper respiratory problems, influenza, viral gastroenteritis, rhinitis, pharyngitis or mild dermatologic problems were among the illnesses that astronauts faced during Apollo spaceflights. Reactivation of varicellas zoster virus, herpes virus and shedding of Epstein–Barr virus was also found in space shuttle crew members.
In astronauts of the Mir station, analyses demonstrated a significant number of episodes of microbial infections, including conjunctivitis, acute respiratory events and dental infections. Future Perspective: Considering Probiotics as a Countermeasure
On Earth, probiotics have been shown to improve both innate and adaptive immune responses. Oral bacteriotherapy with probiotic bacterial strains is believed to improve the intestine's immunologic barrier, particularly through intestinal IgA responses and alleviation of inflammatory reactions. A gut-stabilizing effect seems to occur through a balance between proinflammatory and anti-inflammatory cytokines.
Lactobacillus rhamnosus GG has been shown to inhibit TNF-α-induced IL-8 secretion of human colon adenocarcinoma (HT29) cells and to reduce elevated fecal concentration of TNF-α in patients with atopic dermatitis and cow milk allergy. On the other hand, ingestion of lactobacilli in fermented milk products or as live-attenuated bacteria potentiated the IFN-γ production by peripheral blood mononuclear cells.
Oral administration of lactobacilli increased the systemic and mucosal IgA response to dietary antigens. Oral supplementation with Bifidobacterium bifidum and Bifidobacterium breve enhanced the antibody response to ovalbumin and stimulated the IgA response to cholera toxin in mice. An increase in the humoral immune response including an increase in rotavirus-specific antibody-secreting cells in the IgA class was also detected in children and individuals receiving L. rhamnosus GG.
Isolauri et al. reported that infants receiving a reassortant live oral rotavirus vaccine in conjunction with L. rhamnosus GG had a higher frequency of rotavirus-specific IgM class antibody-secreting cells. An increased incidence of rotavirus-specific IgA antibody class seroconversion compared with placebo subjects was also seen. IgA+ cells and IL-6-producing cells increased in number after 7 days of Lactobacillus casei administration.
In another study, administration of lactic acid bacteria stimulated the gut immune cells to release inflammatory cytokines such as TNF-α, IFN-γ and IL-12, and regulatory cytokines like IL-4 and IL- 10 in a dose- and strain-dependent manner. Several lactobacilli strains have been shown to promote the immunopotentiator capacity of cells of the innate immune system, including macrophages. Examples of probiotics that can modulate the gut immune system are abundant and have been reviewed extensively.
Buckley et al. have suggested that consumption of soy-based fermented products (containing lactic acid bacteria) can prevent the health problems of astronauts associated with long-term space travel. Assessment of soy-based fermented products by in vitro challenge system (using TNF-α) with human intestinal epithelial and macrophage cell lines has demonstrated the ability of the intervention to downregulate production of the proinflammatory cytokine IL-8.
Considering the importance of the human gut in healthy digestion, nutrient absorption and exposure to pathogens across its large surface area, a healthy digestive tract is important to a healthy human. Diet, lifestyle, antibiotic therapy, different kinds of stressful conditions and so on, can exert alterations in an astronaut's gut microbiome in space.
Considering potential immune system alterations from gut microflora changes, antibiotic use in orbit and changes of increased virulence and antibiotic resistance of bacteria in space, physicians who care for astronauts must remember the importance of the intestinal microbiome to their health status. From this perspective, an impaired digestive system might endanger the mission as well as the health of the astronaut. One countermeasure to be considered would be replenishing the astronaut's intestinal microflora by introducing immune-enhancing probiotic bacteria periodically during the mission.
Diet, lifestyle, antibiotic therapy and various environmental stresses, and so on, can exert alterations in an astronaut's gut microbiome in space and impair their immune system.
Although single probiotics have sometimes been shown to promote health, the human microbiome is composed of more than 400 microbial species, most of which remain uncultured and have as yet unknown functions. The Human Microbiome Project will certainly pave the way for us to increase our understanding of these microbial entities.[4] Thus, providing only a single probiotic might not be the answer.
Contrary to numerous previous investigations and clinical trials in which only effects of single or a couple of probiotics have been studied, we think multiprobiotic therapy and/or designing individualized probiotic kits seems a more reasonable option. A series of experiments need to be launched to confirm the efficacy and safety of using probiotics in space.
Safety studies are of equal importance as efficacy studies, since astronauts are immunocompromised (although as discussed above, much of this may return to washing out of microflora in space). These studies can be carried out initially in ground-based space analogs and further followed in actual space (first on animal models and then on humans). The lifestyle of astronauts can be simulated in these studies and after interventions; the composition of microbiota (including opportunistic pathogens) along with immunological markers should be determined.
Both short- and long-term confinement and actual spaceflight studies can be designed. The administration and/or consumption of probiotics is supposed to have immune-enhancing effects, hinder alterations in the human microbiome to a large extent and prevent colonization of potential pathogens. Upon observation of possible benefits, probiotics can be incorporated into astronauts' food or supplied periodically as a probiotic kit.
This line of research can be followed by NASA scientists and other space agencies to enhance the quality of life of astronauts and to contribute to human presence in space.
Surprisingly, this may bring a future where astronauts utilize probiotic bacteria to counteract the potential effect of pathogenic bacteria during spaceflight.
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‘Human Microbiome’ is an abstracted artwork of the human age wise microbial load and its impact on our life. Research data reflects that we come on the earth with microbes and die with microbes. They have coevolved with us and reside in and our body to develop a host-associated structure, called “Microbiome or Microbiota or Commensal microflora or normal microflora. Our body has a nearly equal number of bacteria and our body cells. The establishment of the microbiome begins with birth and matures with age as shown in the agar plate. We are long-term beneficial and enriched media of microbiota and thus, natural agar art of nature. Microbial launch and the establishment of the microbiome is an arbitrary process determined by various factors like mode of delivery, diet, sex, age, genetics, geographic location have a powerful impact in shaping human microbiome structure likewise we provide pH, electrolytes, nutrients, incubation temperature to keep the viability of the microbes in the agar plate. These microbes are in symbiotic association, other than the gut they are also occurred in the mouth, respiratory tract, vagina, and skin. There is growing evidence that imbalances in the microbial communities are connected to many conditions, such as inflammatory bowel disease, allergies, asthma, diabetes, and obesity. It is an era of research to collect information and the relationship among commensal microflora, host, and pathogen to develop safe and effective prophylactics and therapeutics against pathogens. Avoid irrational use of drugs to save our microbiome and live a long healthy life.
Illustration shows the changing microbes in a maturing cheese and some of the factors that affect the microbiota.
As a cheese matures, the lactic acid bacteria and other early colonists give way to other species of bacteria and, eventually, fungi, in a process known as ecological succession. The details of which species are present depend on exactly how the cheese is made and ripened, and what variety it is.
Read more in Knowable Magazine
Blessed are the (tiny) cheesemakers
Cheese is not just a tasty snack — it’s an ecosystem. And the fungi and bacteria within that ecosystem play a big part in shaping the flavor and texture of the final product.
https://knowablemagazine.org/article/food-environment/2022/blessed-are-tiny-cheesemakers
Take a deeper dive: Selected scholarly reviews
New Insights into Cheese Microstructure
Microstructure plays an essential role in the development of cheese products and microscopy can help with that.
https://www.annualreviews.org/doi/10.1146/annurev-food-032519-051812
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Woodside Plaza is dedicated to the members of the Woodside community who served and died in World War I (1914-1918), World War II (1939-1945), Korea (1950-1953), and Vietnam (1964-1975). It is named for the neighborhood of Woodside, which lies in northwestern Queens, abutting Long Island City.
During New York’s colonial period, Woodside was known as “suicide’s paradise,” as it was largely snake-infested swamps and wolf-ridden woodlands. The Dutch gave Father John Doughty, a colonist from Massachusetts, a charter for 13,000 acres in 1642, and thus began the region’s settlement. During the mid-1800s, several wealthy men moved from Charleston, South Carolina to build mansions in the region, including John Kelly. Kelly’s son John Andrew Kelly worked as a newspaper man and wrote a set of articles entitled “Letters from Woodside,” after his view of the woods from his window. When developer Benjamin Hitchcock bought the Kelly estate in 1867 to develop a village, he favored the name Woodside over “suicide’s paradise” for his new town.
Woodside saw a huge building boom in 1869, when Hitchcock broke the Kelly farm into lots, which he sold for between $100 and $300 each. He also built streets in the village, and his interest encouraged other builders to join in developing the area. Eventually, other large estates were sold and developed. The Long Island and the Flushing Rail Road companies merged and opened a station in Woodside in 1895. When the Queensboro Bridge opened in 1909, the population of Woodside rose to nearly six thousand people. Elevated train lines branched into the neighborhood and opened in 1917, causing the population to jump again. In the 1920s, the last tracts of undeveloped land disappeared. After World War II, many of the houses in Woodside were torn down to make way for apartment buildings.
Woodside Plaza, located at the junction of Roosevelt Avenue, Woodside Avenue, and 60th Street, was originally known as Woodside Memorial Park after its construction in 1971. Commissioner Stern renamed the property “Woodside Plaza” in 1998. There is a large monument in the park, made of smooth gray marble, with the following inscription in gold lettering: “WOODSIDE MEMORIAL PARK: Dedicated to all members of the community who made the supreme sacrifice for the good and welfare of their country and for the peace and freedom of mankind. THE WORLD WARS, KOREA, AND VIETNAM.”
Also in the park are several young trees and new plantings including Willowleaf cotoneaster (Cotoneaster salicifolius), Siberian cypress (Microbiota decussata), lillyturf (Liriope muscari “Big Blue”), cranesbill (Geranium masculatum), Bloody geranium (Geranium sanguineum), Evergreen barrenwort (Epidium davidii), Threadleaf bluestar (Amsonia hubrechtii), Meadow sage (Salvia pratensis), and comfrey (Symphytum officinale).
The property is paved with square and hexagonal tiles. There are several sets of wooden benches, as well as two lampposts, a flagpole with a yardarm, and a drinking fountain, all of which were added during reconstruction in 1999. Woodside Plaza is now part of the Greenstreets program, a joint project of Parks and the Department of Transportation begun in 1986 and revived in 1994. Its goal is to convert paved street properties, such as triangles and malls, into green spaces.
Woodside Plaza is dedicated to the members of the Woodside community who served and died in World War I (1914-1918), World War II (1939-1945), Korea (1950-1953), and Vietnam (1964-1975). It is named for the neighborhood of Woodside, which lies in northwestern Queens, abutting Long Island City.
During New Yorks colonial period, Woodside was known as suicides paradise, as it was largely snake-infested swamps and wolf-ridden woodlands. The Dutch gave Father John Doughty, a colonist from Massachusetts, a charter for 13,000 acres in 1642, and thus began the regions settlement. During the mid-1800s, several wealthy men moved from Charleston, South Carolina to build mansions in the region, including John Kelly. Kellys son John Andrew Kelly worked as a newspaper man and wrote a set of articles entitled Letters from Woodside, after his view of the woods from his window. When developer Benjamin Hitchcock bought the Kelly estate in 1867 to develop a village, he favored the name Woodside over suicides paradise for his new town.
Woodside saw a huge building boom in 1869, when Hitchcock broke the Kelly farm into lots, which he sold for between $100 and $300 each. He also built streets in the village, and his interest encouraged other builders to join in developing the area. Eventually, other large estates were sold and developed. The Long Island and the Flushing Rail Road companies merged and opened a station in Woodside in 1895. When the Queensboro Bridge opened in 1909, the population of Woodside rose to nearly six thousand people. Elevated train lines branched into the neighborhood and opened in 1917, causing the population to jump again. In the 1920s, the last tracts of undeveloped land disappeared. After World War II, many of the houses in Woodside were torn down to make way for apartment buildings.
Woodside Plaza, located at the junction of Roosevelt Avenue, Woodside Avenue, and 60th Street, was originally known as Woodside Memorial Park after its construction in 1971. Commissioner Stern renamed the property Woodside Plaza in 1998. There is a large monument in the park, made of smooth gray marble, with the following inscription in gold lettering: WOODSIDE MEMORIAL PARK: Dedicated to all members of the community who made the supreme sacrifice for the good and welfare of their country and for the peace and freedom of mankind. THE WORLD WARS, KOREA, AND VIETNAM.
Also in the park are several young trees and new plantings including Willowleaf cotoneaster (Cotoneaster salicifolius), Siberian cypress (Microbiota decussata), lillyturf (Liriope muscari Big Blue), cranesbill (Geranium masculatum), Bloody geranium (Geranium sanguineum), Evergreen barrenwort (Epidium davidii), Threadleaf bluestar (Amsonia hubrechtii), Meadow sage (Salvia pratensis), and comfrey (Symphytum officinale).
The property is paved with square and hexagonal tiles. There are several sets of wooden benches, as well as two lampposts, a flagpole with a yardarm, and a drinking fountain, all of which were added during reconstruction in 1999. Woodside Plaza is now part of the Greenstreets program, a joint project of Parks and the Department of Transportation begun in 1986 and revived in 1994. Its goal is to convert paved street properties, such as triangles and malls, into green spaces.
By now, we all know that breastfeeding is liquid gold. It is the best food and in ideal circumstances, should be the only food for your baby during his or her first 6 months of life. More than just providing nutrition, it provides antibodies, growth hormones and supports in developing a healthy gut microbiota in your little one!
Read more - relacto.com.sg/blog/how-to-build-a-great-milk-supply-for-...