View allAll Photos Tagged buoyancy
During sunset, a cloud flew in in an amazing shape (a bird, a dragon, and maybe an angel ...)
A little understanding of the physics of cloud formation underscores the complexity of the atmosphere and sheds light on why predicting weather for more than a few days is such a challenge.
Six types of clouds you can see and how they can help you understand the weather.
1) Cumulus clouds - On a sunny day, rays warm the earth, which heats the air located directly above it. The heated air rises upward due to convection and forms cumulus clouds. These “good weather” clouds are like cotton wool. If you look at the sky filled with cumulus clouds, you can see that they have a flat bottom, located at the same level for all clouds. At this altitude, air rising from ground level cools down to the dew point. It usually doesn't rain from cumulus clouds, which means the weather will be good.
2) Cumulonimbus clouds.
Small cumulus clouds do not rain, but if they grow and grow in height, it is a sign that heavy rain is coming soon. This often happens in summer when morning cumulus clouds turn into cumulonimbus during the day. Cumulonimbus clouds often have a flat top. Air convection occurs inside such a cloud, and it gradually cools until it reaches the temperature of the surrounding atmosphere. At this moment, it loses its buoyancy and can no longer rise higher. Instead, it spreads out to the sides, forming the characteristic anvil shape.
3) Cirrus clouds form in very high layers of the atmosphere. They are smoky because they are composed entirely of ice crystals falling in the atmosphere. When cirrus clouds are carried by winds moving at different speeds, they take on a characteristic curved shape. And only at very high altitudes or at high latitudes, cirrus clouds give out rain that reaches the ground.
4) Stratus Clouds - A low-lying, continuous cloud sheet that covers the sky. Stratus clouds are formed by slowly rising air or gentle winds that cover the cold land or sea surface with moist air. Stratus clouds are thin, therefore, despite the gloomy picture, it is unlikely to rain from them, a little drizzle at most. Stratus clouds are identical to fog, so if you've ever walked in a mountainous area on a foggy day, you've been inside a cloud.
5) Lenticular clouds. Smooth and lenticular lenticular clouds form when air is blown up and over a mountain range, and as it travels over a mountain, the air descends to its previous level. At this time, it heats up and the cloud evaporates. But it can slip further, as a result of which the air rises again and forms another lenticular cloud. This can result in a chain of clouds extending far beyond the mountain range. The interaction of wind with mountains and other surface features is one of the many details that must be taken into account in computer simulations to obtain accurate weather predictions.
6) Kelvin - Helmholtz like a breaking ocean wave. When air masses at different heights move horizontally at different speeds, their state becomes unstable. The boundary between the air masses begins to ripple and form large waves, such clouds are quite rare.
The photo was taken in the city of Konakovo. Russia. On the banks of the Volga River.
An Anhinga in all its mating glory colors and feathers
A long-necked, long-tailed swimmer of southeastern swamps. Often seen perched on a snag above the water, with its wings half-spread to dry. Can vary its buoyancy in water, sometimes swimming with only head and neck above water (earning it the nickname of 'Snakebird'). Often solitary when feeding, it roosts in groups and nests in colonies. Looks rather like a cormorant when perched, but not in flight, when the long tail may be spread wide as the Anhinga soars high on outstretched wings. Anhingas are silent at most times, but around nesting colonies they make various croaking and clicking sounds.
I shot this with a flash using a MagMod at -1.3 f-stops to fill in the shadows of the black feathers and provide some detail - which I usually don't do, but it seems to have worked here.
This Common Loon photo was take on a lake in Alberta, Canada.
An interesting fact of of these birds are that they are solid rather than air filled like other birds.
Loons heavy bones reduce their buoyancy, which makes it easier for them to dive. Loons can dive as deep as 60 meters.
-Gavia immer
Naples Botanical Gardens
Southeaster Florida
USA
The Pied-billed Grebe is common across much of North America. These small brown birds have unusually thick bills that turn silver and black in summer. These expert divers inhabit sluggish rivers, freshwater marshes, lakes, and estuaries. They use their chunky bills to kill and eat large crustaceans along with a great variety of fish, amphibians, insects, and other invertebrates.
Rarely seen in flight and often hidden amid vegetation, Pied-billed Grebes announce their presence with loud, far-reaching calls.
With feet located near their rear ends which is a common feature of many diving birds, this helps grebes propel themselves through water. Lobed (not webbed) toes further assist with swimming.
Pied-billed Grebes can trap water in their feathers, giving them great control over their buoyancy. They can sink deeply or stay just at or below the surface, exposing as much or as little of the body as they wish.
When in danger, Pied-billed Grebes sometimes make a dramatic “crash-dive” to get away. - Wikipedia
One of the many South American sea lions (Otaria flavescens) that hang around the fish stalls in the port of Punta del Este. Mostly males, they wait for either the public or the vendors to throw fish to them. Occasionally the seagulls venture to steal the food from their mouths... They offer a good show.
• South american sea lion / patagonian sea lion
• Lobo marino de un pelo
Scientific classification
Kingdom:Animalia
Phylum:Chordata
Class:Mammalia
Order:Carnivora
Suborder:Pinnipedia
Family:Otariidae
Subfamily:Otariinae
Genus:Otaria
Species:O. flavescens
Puerto de Punta del Este, Maldonado, Uruguay
Darters (Anhinga novaehollandiae) are a water bird closely related to Cormorants. Their feathers are not waterproof and since they are underwater hunters they are often seen sitting out of the water on a log or rock with their wings spread out drying themselves. Their feathers are permeable to water to allow for decreased buoyancy so they can sink to catch their prey. They have very long and sharp beaks, which they use with their long neck to spear their prey. I saw this one in Lake Burley Griffin, Canberra.
This Pied Billed Grebe was watching the other birds on the pond from a partially submerged vantage before fully submerging to look for food for the babies.
When ducks dive under the water, they must leap forward and stroke powerfully with their feet to overcome their inherent buoyancy. The grebe, however, is the master of its own buoyancy. It can squeeze out the air trapped in its feathers and internal air-sacs, and sink effortlessly.
This photo was taken near Cochrane, Alberta Canada
-Podilymbus podicep
A typical view seen near the top of Beartooth Pass. The flat plateaus, alpine cirques, U-shaped valleys and lakes of the Beartooths were sculpted by glaciers. Truly a remarkable and fascinating geological wonder.
A trip over the Beartooth Pass is not only a soaring adventure via car, it is a trip back in time to some of the earliest glimpses of Earth history. This is history you can stand on, with some of the oldest rocks on Earth, uplifted to their present height by tectonic forces and Yellowstone’s thermal buoyancy, and finally artistically shaped by persistent weathering and glacial erosion.
Thanks for taking a look. Always appreciated!
Have a wonderful Friday and weekend!
An Anhinga from the underside.
From Animalia:
The anhinga is found in warmer regions of the Americas. Being members of the family of darters, they are related to cormorants and pelicans. "Anhinga" come from the Tupi language of Brazil and means snake bird or devil bird. These Central and North American birds are skilful swimmers with unique characteristics that help them when hunting for fish. With a large wing span, they are able to fly in the manner of a vulture or a hawk. Males and females look different, with the females being smaller and browner and the males blacker. Their feathers provide less buoyancy than ducks, so they are able to dive under the water, and swim with just their thin necks above the water, earning them the nickname of the "snake bird".
From the photographer - the Anhinga has an amazing webbed claw foot - as you can see they can easily grab a branch with their claws - but their webbing helps make them adept swimmers.
This was only ever going to be a test shot, taken to prove my settings and wrist action, but my humorous side got the better of me......... a "nice song" by a very nice lady.
This Cormorant explodes from the surface of the water on take off . The Cormorant is a large, black, fish-eating bird with a long, hook-tipped bill. When on water they swim low with their bill raised, and often dive with a leap from the water's surface. Their plumage is not waterproof but this has the advantage of allowing them to dive deep, as buoyancy is reduced.
A floating dry dock is a type of pontoon for dry docking ships, possessing floodable buoyancy chambers and a "U"-shaped cross-section. The walls are used to give the dry dock stability when the floor or deck is below the surface of the water. When valves are opened, the chambers fill with water, causing the dry dock to float lower in the water. The deck becomes submerged and this allows a ship to be moved into position inside. When the water is pumped out of the chambers, the dry dock rises and the ship is lifted out of the water on the rising deck, allowing work to proceed on the ship's hull.
en.wikipedia.org/wiki/Dry_dock
www.blohmvoss.com/en/corporate/content/blohm-voss/docks-f...
This cute little character is a Pied-billed Grebe. These small birds are expert divers that make their living underwater, capturing crustaceans, fish, amphibians and insects. By trapping water in their feathers, Pied-billed Grebes have the ability to alter their buoyancy, says AllAboutBirds.org, This aids in feeding and allows them when threatened to float with just their head above water. Breeding adults such as this one have a vertical black stripe on their bill.
Species: Phalacrocorax carbo.
The Cormorant is a large, black, fish-eating bird with a long, hook-tipped bill. They can be seen on both coastal and inland waters. When on water they swim low with their bill raised, and often dive with a leap from the water's surface. Their plumage is not waterproof but this has the advantage of allowing them to dive deep, as buoyancy is reduced. Info: BTO.
Many thanks to people who view or comment on my photos
Click to view Large.
The pied-billed grebe may mimic the movements of a duck in water but this bird does not have webbed feet. Instead its toes have lobes extending out from the sides, which makes it a swimmer to rival any duck. The pied-billed grebe is pigeon sized, brownish in color and has a chicken-like beak.
Pied-billed Grebes can adjust their buoyancy and often use this ability to float with just the upper half of the head above the water. They catch small fish and invertebrates by diving or simply slowly submerging. They build floating nests of cattails, grasses, and other vegetation.
These are brown birds, slightly darker above and more tawny-brown on the underparts. During spring and summer, the crown and nape are dark and the throat is black. While breeding, the bill is whitish with a black band (“pied’), but otherwise is yellow-brown. Juveniles have striped faces.
Taken at Sandy Camp Rd Wetlands Reserve, Lytton,Qld.
The arrangement of contour feathers plus the oil from uropygial glands spread across contour feathers, repels water effectively to keep a bird dry. Crucial for birds that spend much of their time submerged in water.
Contour feathers contain air spaces between the barbs and barbules. This, and the shape of the barbs and barbules, gives feather's their water-repelling qualities.
Some waterbirds have a tighter arrangement of barbs and barbules, creating smaller airspaces and therefore less buoyancy. Diving birds such as cormorants and anhingas benefit from this by carrying fewer air bubbles trapped in their feathers. With less air on board these diving birds can dive more efficiently and swim faster than those with more trapped air!
The downside is that these birds must spend some time drying out their wings after a fishing session to offload all the extra moisture contained in their plumage. This is especially important before the nightfall drop in temperature!
A lava lamp is a decorative lamp, invented in 1963 by British entrepreneur Edward Craven Walker, the founder of the lighting company Mathmos.
It consists of a bolus of a special coloured wax mixture inside a glass vessel, the remainder of which contains clear or translucent liquid. The vessel is placed on a base containing an incandescent light bulb whose heat causes temporary reductions in the wax's density and the liquid's surface tension.
As the warmed wax rises through the liquid, it cools, loses its buoyancy, and falls back to the bottom of the vessel in a cycle that is visually suggestive of pāhoehoe lava, hence the name. The lamps are designed in a variety of styles and colours.
Lava lamps are often associated with hippie culture and cannabis culture.
This little one was in small space of open water at a marina / harbour. It made it easier for me to locate him every time he resurfaced after diving in search of food. They can sink like a little submarine by squeezing all the air out of their feathers and out of their internal air sacs. Unlike other diving ducks they can regulate their buoyancy which is an advantage when fishing underwater, they can swim just under the surface or go deeper with little effort.
As a youngster, I was amazed that a small pebble would sink, and a big block of wood, would float... I was even more amazed by seagoing vessels, and this large ship and small floating dock reminded me of those days! Today, with some knowledge of density, volume displacement, buoyancy and Archimedes' Principle, the subject matter is still intriguing!
Galileo Thermometer
Macro Mondays theme: Balance
Here, the temperature-dependent buoyancy of the glass sphere is balanced by the gravitational force.
Three focus-stacked images. For an image with scale, see here:
Naples Botanical Gardens
Southeaster Florida
USA
The Pied-billed Grebe is common across much of North America. These small brown birds have unusually thick bills that turn silver and black in summer. These expert divers inhabit sluggish rivers, freshwater marshes, lakes, and estuaries.
They use their chunky bills to kill and eat large crustaceans along with a great variety of fish, amphibians, insects, and other invertebrates. Rarely seen in flight and often hidden amid vegetation, Pied-billed Grebes announce their presence with loud, far-reaching calls.
Their feet are located near their rear ends. This body plan, a common feature of many diving birds, helps grebes propel themselves through water. Lobed (not webbed) toes further assist with swimming. Pied-billed Grebes pay for their aquatic prowess on land, where they walk awkwardly. Pied-billed Grebes are poor fliers and typically stay on the water.
Pied-billed Grebes can trap water in their feathers, giving them great control over their buoyancy. They can sink deeply or stay just at or below the surface, exposing as much or as little of the body as they wish. The water-trapping ability may also aid in the pursuit of prey by reducing drag in turbulent water. - Wiklipedia
New Zealand endemic diving duck. Widely but patchily distributed throughout North and South Islands; not found on Stewart Island, and no longer present on Chatham Islands. Unlike any other resident duck species. Compact and dark; floats on water with cork-like buoyancy, showing bath-toy duck silhouette. Forms large flocks, often congregating in sheltered areas near willows or reed beds. Spends a lot of time underwater, where it can travel considerable distances. Sexes alike but distinguishable. Male has dark black plumage, iridescent blue-green head and wings, and yellow iris. Female is duller brown with brown iris. Flies with very fast wingbeats, often just above the water’s surface. Vagrant Hardhead differs in its white iris, white undertail, and white “saddle” on bill. (eBird)
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Common throughout our trip, but like with most scaup, usually just far enough away to make photos uninteresting. This beautiful male kindly picked a lovely sunny day to present his best side. He was keeping an eye on his offspring, closer to shore.
Wanaka, Otago, New Zealand. March 2024.
Roadrunner Birding Tours.
Some facts on the elegant Montagu's Harrier
- When the chicks have hatched, the female won’t allow the male near the nest. Instead, the male will drop the food from above the nest.
- The Montagu’s harrier is a graceful flier due to their large wingspan that provides buoyancy and elegance.
- The Montagu’s harrier is named after the British naturalist George Montagu, who paved the way for defining bird species with his 1802 book, the Ornithological Dictionary.
Montagu's Harrier (Circus pygargus) adult male hunting_3657
The leaf is composed of layers of cells. The spongy mesophyll layer is normally infused with gases, oxygen and carbon dioxide. Leaves (or disks cut from leaves) will normally float in water because of these gases. If you draw the gases out from the spaces, then the leaves will sink because they become more dense than water. If this leaf disk is placed in a solution with an alternate source of carbon dioxide in the form of bicarbonate ions, then photosynthesis can occur in a sunken leaf disk. As photosynthesis proceeds, oxygen accumulates in the air spaces of the spongy mesophyll and the leaf becomes buoyant and floats. Oxygen and carbon dioxide are exchanged through openings in the leaf called stoma.
While this is going on, the leaf is also carrying out cellular respiration. This respiration will consume the oxygen that has accumulated and possibly cause the plant disks to sink. The measurement tool that can be used to observe these counteracting processes is the floating (or sinking) of the plant disks. In other words, the buoyancy of the leaf disks is actually an indirect measurement of the net rate of photosynthesis occurring in the leaf tissue.
All that being said... Ain't it pretty?
Thanks for looking?
reference:
Click image to view Larger.
Pied-billed Grebes can adjust their buoyancy and often use this ability to float with just the upper half of the head above the water. They catch small fish and invertebrates by diving or simply slowly submerging. They build floating nests of cattails, grasses, and other vegetation.
These are brown birds, slightly darker above and more tawny-brown on the underparts. During spring and summer, the crown and nape are dark and the throat is black. While breeding, the bill is whitish with a black band (“pied’), but otherwise is yellow-brown. Juveniles have striped faces.
Pied-billed Grebes can trap water in their feathers, giving them great control over their buoyancy. They can sink deeply or stay just at or below the surface, exposing as much or as little of the body as they wish. (CornellLab)
Caught this Grebe shortly after returning to the surface.
Click photo to view large.
Pied-billed Grebes can adjust their buoyancy and often use this ability to float with just the upper half of the head above the water. They catch small fish and invertebrates by diving or simply slowly submerging. They build floating nests of cattails, grasses, and other vegetation.
Look for Pied-billed Grebes on small, quiet ponds and marshes where thick vegetation grows out of the water. In winter they occur on larger water bodies, occasionally in large groups.
Do you like a story? Would you like to hear, or should I say read, the story behind this one? Okay if you insist :)
See the pointy rock to the right, then see the big rock to its left? If you blow the photo up large and look closely just to its left, you’ll notice a small boat. That boat, the "SS Oxidation" belongs to Rusty Malloy. Good old Rusty.
Not many people know this, but Rusty has a sister named Bree. Bree is ... spirited. Rebellious could be another word for it. As younger sisters sometimes are (I hope mine isn’t reading this). When Bree herself was younger she briefly dated a local hooligan who went by the nickname Knuckles. Real piece of work, Knuckles.
One afternoon Knuckles thought he would try & impress Bree by acting tough on a train, giving a hard time to a quiet young couple named Hugh & June. June, as it turns out, was an upcoming gymnast - very promising. There was talk she might even make the Olympic team one day. She believed gravity was mostly a guideline and flat surfaces a career opportunities. June's biggest supporter in her endeavours was her hard-working, salt of the earth, father Arthur.
Arthur, worked at a plant nursery called The Little Shop of Growers. Model employee. Employee of the Month several times, chosen personally by the boss, Mossy Greenwell, a woman who trusted three things: compost, clipboards, and hard-working, salt of the earth people.
Arthur used to carpool to work with Nettle, the nursery’s bookkeeper. Nettle had a strong dislike of silence and always had talkback radio blaring on the ride to work. One morning, while stuck in traffic, they heard a segment about underappreciated Olympic sports like - you can guess what, hey! - gymnastics! This inspired Arthur to buy June a second-hand balance beam off a bloke named Colin.
Still with me, stick with it ;)
Colin repaired kayaks on weekends. He once mentioned, during a very long explanation about epoxy & resin, (yes, I used to try & fix my own surfboards so like stuff about epoxy & resin is interesting. In particular how to get it off your hands when you are covered in it. Anyway, sorry for digressing. Good word "digress" especially when you say it slow and meaningfully. Sorry , digressed again) that his cousin, Anita Bath, worked in coastal erosion management, specialising in dune rehabilitation and native grass planting.
Soooo, Anita later consulted on a small, low-budget shoreline stabilisation project. At a little-known beach known as Gravelly Beach on the Central Coast. Right here!
To cut a long story short, in case you are falling asleep, those grasses helped stabilise the sand, which protected the shoreline, which reduced erosion, which meant fewer rocks breaking off into the water, which made boating safer.
And this of course brings us back to one particular small boat. A very special one. The "SS Oxidation".
I had to tell you this story because the SS is such a key element of this photo, and without those exceptional circumstances, it may not have been participating quite as well in buoyancy as seen here. And that would have ruined the whole photo.
Have a great start to your Christmas week everyone! Thanks for any comments, always appreciated :)
PS: This explanation exists mainly for narrative convenience and should not be fact-checked too closely ;)
Endemic and common in New Zealand. There is a small population of them on the Kaiapoi River.
New Zealand scaup are gregarious diving ducks. are quite unlike any other resident duck species. Dark and squat with a rounded profile, they often occur in large flocks, floating with cork-like buoyancy. Scaup are diving ducks and spend a lot of time underwater, where they can travel considerable distances.
The Australian pied cormorant (Phalacrocorax varius), also known as the pied cormorant, pied shag, or great pied cormorant, is a medium-sized member of the cormorant family. It is found around the coasts of Australasia. In New Zealand, it is usually known either as the pied shag or by its Māori name of kāruhiruhi. Older sources may refer to it as the yellow-faced cormorant. The pied cormorant is predominantly black on its back and upper surface of the wings and white on the underside with males weighing approximately 2.2 kg and females 1.7 kg. It stands between 65–85 cm tall, with a wingspan of 110–130 cm. A small yellow patch between the bill and the eye on each side of the head is likely to have been the reason for the historical common name. It has large webbed feet which it utilises to pursue fish underwater, steering with half opened wings. The bird has a large hooked bill, green eyes with a blue eye ring and black legs and feet. The eyes have a special nictitating membrane for underwater protection. The pied cormorant can often be seen spreading its wings after diving to help dry the feathers, as it has inadequate waterproofing. This lack of feather waterproofing may help the cormorant spend longer underwater due to decreased buoyancy effects. 40773
Naples Botanical Gardens
Southeaster Florida
USA
Part bird, part submarine, the Pied-billed Grebe is common across much of North America. These small brown birds have unusually thick bills that turn silver and black in summer. These expert divers inhabit sluggish rivers, freshwater marshes, lakes, and estuaries. They use their chunky bills to kill and eat large crustaceans along with a great variety of fish, amphibians, insects, and other invertebrates. Hidden amid vegetation, Pied-billed Grebes announce their presence with loud, far-reaching calls.
The grebes feet are located near their rear ends. This body plan, a common feature of many diving birds, helps grebes propel themselves through water. Lobed (not webbed) toes further assist with swimming. Pied-billed Grebes pay for their aquatic prowess on land, where they walk awkwardly.
Pied-billed Grebes are fairly poor fliers and typically stay on the water—although rare individuals have managed to fly as far as the Hawaiian Islands, Europe, and the Azores.
Pied-billed Grebes can trap water in their feathers, giving them great control over their buoyancy. They can sink deeply or stay just at or below the surface, exposing as much or as little of the body as they wish. The water-trapping ability may also aid in the pursuit of prey by reducing drag in turbulent water.
When in danger, Pied-billed Grebes sometimes make a dramatic “crash-dive” to get away. A crash-diving grebe pushes its body down with its wings thrust outward. Its tail and head disappear last, while the bird kicks water several feet into the air. – Wikipedia
The one just left of centre kept trying to dive like Mum but its buoyancy wouldn't let it.
Thank you to all who take the time to visit and comment or fave my images. It is much appreciated.
The weather has been pretty miserable here the last couple of days and I have been feeling miserable with a cold (for 3 weeks now), so I am going back through my archives.
Darters are a water bird that is closely related to Cormorants. Their feathers are not waterproof and since they are underwater hunters you will usually see them sitting out of the water on a log or rock with their wings spread right out drying themselves. Their feathers are permeable to water to allow for decreased buoyancy so they can sink to catch their prey. They have an oil gland at the base of their tail which they use while preening and squeezing the water from their feathers. With its body submerged and only its head and neck above the surface, the Darter resembles a snake rising from the water; hence one of its popular names the Snake-bird. They have very long and sharp beaks, which they use with their long neck to spear their prey.
#380 on Explore on 17th April, 2008.
This is one species I never had the chance to observe much as we rarely see them in our area and, furthermore, it doesn't stick around long.
Needless to say I was extremely excited to see this little cutie but it took me a very long time to get close without disturbing him or her.
At two occasions, this Grebe went down in the water this way, it was so strange to watch as if it was diving in a very shallow water.
So when I got back home I did some research and here is what I found in ''All about Birds'': Pied-billed Grebes can adjust their buoyancy and often use this ability to float with just the upper half of the head above the water. They catch small fish and invertebrates by diving or simply slowly submerging. They build floating nests of cattails, grasses, and other vegetation.
That was so awesome to see. Unfortunately, it was just passing by for the day.
Naples Botanical Gardens
Southeastern Florida
USA
Part bird, part submarine, the Pied-billed Grebe is common across much of North America. These small brown birds have unusually thick bills that turn silver and black in summer.
These expert divers inhabit sluggish rivers, freshwater marshes, lakes, and estuaries. They use their chunky bills to kill and eat large crustaceans along with a great variety of fish, amphibians, insects, and other invertebrates.
Rarely seen in flight and often hidden amid vegetation, Pied-billed Grebes announce their presence with loud, far-reaching calls.
Lobed (not webbed) toes assist with swimming. Pied-billed Grebes pay for their aquatic prowess on land, where they walk awkwardly.
Pied-billed Grebe chicks typically leave the nest the first day after hatching and spend much of their first week riding around on a parent’s back.
Pied-billed Grebes are fairly poor fliers and typically stay on the water.
Pied-billed Grebes can trap water in their feathers, giving them great control over their buoyancy. They can sink deeply or stay just at or below the surface, exposing as much or as little of the body as they wish. When in danger, Pied-billed Grebes sometimes make a dramatic “crash-dive” to get away. A crash-diving grebe pushes its body down with its wings thrust outward. Its tail and head disappears last, while the bird kicks water several feet into the air. – Wikipedia
The Australian pied cormorant (Phalacrocorax varius), also known as the pied cormorant, pied shag, or great pied cormorant, is a medium-sized member of the cormorant family. It is found around the coasts of Australasia. In New Zealand, it is usually known either as the pied shag or by its Māori name of kāruhiruhi. Older sources may refer to it as the "yellow-faced cormorant". The pied cormorant is predominantly black on its back and upper surface of the wings and white on the underside with males weighing approximately 2.2 kg and females 1.7 kg. It stands between 65–85 cm tall, with a wingspan of 110–130 cm. A small yellow patch between the bill and the eye on each side of the head is likely to have been the reason for the historical common name. It has large webbed feet which it utilises to pursue fish underwater, steering with half opened wings. The bird has a large hooked bill, green eyes with a blue eye ring and black legs and feet. The eyes have a special nictitating membrane for underwater protection. The pied cormorant can often be seen spreading its wings after diving to help dry the feathers, as it has inadequate waterproofing. This lack of feather waterproofing may help the cormorant spend longer underwater due to decreased buoyancy effects. 52101
Click image to view Larger.
The pied-billed grebe may mimic the movements of a duck in water but this bird does not have webbed feet. Instead its toes have lobes extending out from the sides, which makes it a swimmer to rival any duck. The pied-billed grebe is pigeon sized, brownish in color and has a chicken-like beak.
Pied-billed Grebes can adjust their buoyancy and often use this ability to float with just the upper half of the head above the water. They catch small fish and invertebrates by diving or simply slowly submerging. They build floating nests of cattails, grasses, and other vegetation.
These are brown birds, slightly darker above and more tawny-brown on the underparts. During spring and summer, the crown and nape are dark and the throat is black. While breeding, the bill is whitish with a black band (“pied’), but otherwise is yellow-brown. Juveniles have striped faces.
John Heinz NWR
Right before a dive, diving ducks flatten their feathers against their skin. Squeezing out the excess air decreases buoyancy.
the Australasian darter or Australian darter (Anhinga novaehollandiae), female
The darter's feathers are not hydrophobic like other birds'. In this way, it has reduced buoyancy and is good at diving and spearfishing. However, the darter cannot simply shake and flap off water from its feathers. Thus, it hangs them out to dry!
The theme for "Smile on Saturday" for the 19th of July is "creative with shells", where as the title suggests, we need to be creative with shells, so do something interesting with them. Now, I do enjoy fossicking along the beaches I visit, and I am known to gather shells. A while ago I came across a large number of cuttlefish bones on one of my walks, so I picked them up and brought them home. I used them to take a few creative photographs and then I got rid of them, as unlike other shells which lose their seaside smell, theirs only intensified because what they are made of is so porous. Now, you might say, “but the theme is about being creative with shells, not bones.” Let me assure you that in spite of their name, cuttlefish bones or cuttlebones are not really bones at all. They are in fact a brittle internal shell of a cuttlefish which allow them to control their buoyancy. Therefore, unless I am told otherwise, I believe this is an acceptable choice for this week’s theme. When I took my photographs, for one, I copied a chromolithographic image of Queen Elizabeth I from one of my Victorian era chocolate advertising cards and enlarged the image. I then covered over The Queen’s stiffened lace ruff with a halo of cuttlefish bones beneath her head. I think that is quite creative enough for this week’s theme. I hope you like my choice for this week’s theme, and that it makes you smile!
Cuttlebone, also known as cuttlefish bone, is a hard, brittle internal structure (an internal shell) found in all members of the family Sepiidae, commonly known as cuttlefish, within the cephalopods. In other cephalopod families it is called a gladius. Cuttlebone is composed primarily of aragonite. It is a chambered structure that the animal can fill with gas or liquid for buoyancy control. On the bottom side of the cuttlebone is the highly modified organ with which the cuttlebone is filled with gas or liquid. The microscopic structure of cuttlebone consists of narrow layers connected by numerous upright pillars. When the cuttlefish dies, only the cuttlebone remains and will often wash up on a beach. In the past, cuttlebones were ground up to make polishing powder, which was used by goldsmiths. The powder was also added to toothpaste, and was used as an antacid for medicinal purposes or as an absorbent. They were also used as an artistic carving medium during the Nineteenth and Twentieth Centuries. Today, cuttlebones are commonly used as calcium-rich dietary supplements for caged birds and are not intended for human consumption.
Anhinga
From Audubon:
A long-necked, long-tailed swimmer of southeastern swamps. Often seen perched on a snag above the water, with its wings half-spread to dry. Can vary its buoyancy in water, sometimes swimming with only head and neck above water (earning it the nickname of 'Snakebird'). Often solitary when feeding, it roosts in groups and nests in colonies. Looks rather like a cormorant when perched, but not in flight, when the long tail may be spread wide as the Anhinga soars high on outstretched wings. Anhingas are silent at most times, but around nesting colonies they make various croaking and clicking sounds.
Anhinga - the Anhinga is among the most distinctive of American birds, with long, snakelike neck, straight bill, large fanlike tail resembling that of a turkey (Meleagris gallopavo; from which the former name Water Turkey was derived), corrugations on its central rectrices, and unique swimming, flight, and behavior patterns. This truly aquatic species spends its life in water or on branches overhanging protected, usually freshwater streams and ponds. Unlike most aquatic birds, Anhingas have fully wettable plumage and dense bones, adaptations that allow them to achieve neutral buoyancy in water, facilitating a slow, stalking hunting habit while submerged in shallow aquatic vegetation, where they spear fish. The neck vertebrae are arranged to allow a strong and rapid stab. While the bird is swimming on the surface, its body is usually submerged, with only the head and snakelike neck visible, making it obvious why the term “snake bird” is often applied. The word “Anhinga” is derived from a Tupi (Brazilian) Indian name, anhingá or anhangá, for the devil bird, an evil spirit of the woods (Jobling Jobling 1991).
Picture taken at Pantanal - Mato Grosso - in black and white for a PMBT!
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Buckpool and Fens Pool Local Nature Reserve
What3Words
///thin.spill.bravo
The cormorant is a family of medium-to-large aquatic birds found worldwide that are expert fishers known for their characteristic posture of standing with wings outstretched to dry.
Appearance:
Cormorants are generally large, dark-plumaged birds with a long, thick, and flexible neck, giving them a somewhat "prehistoric" or "reptilian" appearance. They have a long, thin bill that ends in a sharp hook, perfectly suited for catching fish. Most species have webbed feet with all four toes joined.
Size:
Size varies by species, but the Great Cormorant, a widespread species, typically measures 80-100 cm (31-39 in) in length with a wingspan of 130-160 cm (51-63 in).
Habitat and Distribution: They are highly adaptable and found in a wide variety of aquatic environments, including ocean coasts, estuaries, large rivers, and freshwater lakes and reservoirs across the world, except for the central Pacific islands.
Diet and Hunting: Cormorants are carnivorous, feeding primarily on fish, but also amphibians, crustaceans, and eels. They hunt by diving from the water's surface and propelling themselves underwater using their powerful webbed feet. They can dive to impressive depths, sometimes up to 45 meters (150 feet), and use their hooked bills to seize prey.
Unique Behaviors and Facts
Wing-Drying Posture:
One of the most recognizable cormorant behaviors is perching with their wings spread wide in the sun. This is because their feathers are not fully waterproof (which helps them reduce buoyancy for diving more efficiently), so they need to dry them afterwards.
The Australian pied cormorant (Phalacrocorax varius), also known as the pied cormorant, pied shag, or great pied cormorant, is a medium-sized member of the cormorant family. It is found around the coasts of Australasia. In New Zealand, it is usually known either as the pied shag or by its Māori name of kāruhiruhi. Older sources may refer to it as the yellow-faced cormorant. The pied cormorant is predominantly black on its back and upper surface of the wings and white on the underside with males weighing approximately 2.2 kg and females 1.7 kg. It stands between 65–85 cm tall, with a wingspan of 110–130 cm. A small yellow patch between the bill and the eye on each side of the head is likely to have been the reason for the historical common name. It has large webbed feet which it utilises to pursue fish underwater, steering with half opened wings. The bird has a large hooked bill, green eyes with a blue eye ring and black legs and feet. The eyes have a special nictitating membrane for underwater protection. The pied cormorant can often be seen spreading its wings after diving to help dry the feathers, as it has inadequate waterproofing. This lack of feather waterproofing may help the cormorant spend longer underwater due to decreased buoyancy effects. 12538
It was nap time. Just getting a photo of these precious animals where you might see their features - eyes, ears, nose, mouth - was well nigh impossible. Nevertheless, I hung in there for the better part of a couple of hours, hoping for a wink. So - this image is hard to read - best viewed large. Mom has a pretty large pup floating there at her side, and she has the head cradled on her chest, anchored with her forepaws one on each side. If you look closely, you can pick out the pup's features (viewed upside-down here). Of note, I think is a word about the pup's buoyancy. They are so buoyant at birth, they can't sink. They hang out on mom's chest and don't start swimming for a month, aren't weaned for maybe six months. But notice the buoyancy - the pup looks like it is completely on the water's surface, whereas you can see on the mom a lot of her body is actually below the surface. Pretty interesting.
California's Central Coast, Morro Bay.