Galapagos Islands-694
One of the massive Marine Iguanas on Isabella
Marine Iguana
The Marine Iguana (Amblyrhynchus cristatus) is an iguana found only on the Galapagos Islands that has the ability, unique among modern lizards, to live and forage in the sea. It has spread to all the islands in the archipelago, and is sometimes called the Galapagos Marine Iguana. It mainly lives on the rocky Galapagos shore, but can also be spotted in marshes and mangrove beaches. On his visit to the islands, Charles Darwin was revolted by the animals' appearance, writing “The black Lava rocks on the beach are frequented by large (2-3 ft), disgusting clumsy Lizards. They are as black as the porous rocks over which they crawl & seek their prey from the Sea. I call them 'imps of darkness'. They assuredly well become the land they inhabit.” In fact, Amblyrhynchus cristatus is not always black; the young have a lighter coloured dorsal stripe, and some adult specimens are grey. The reason for the sombre tones is that the species must rapidly absorb heat to minimize the period of lethargy after emerging from the water. They feed almost exclusively on marine algae, expelling the excess salt from nasal glands while basking in the sun, and the coating of salt can make their faces appear white. In adult males, coloration varies with the season. Breeding-season adult males on the southern islands are the most colorful and will acquire reddish and teal-green colors, while on Santa Cruz they are brick red and black, and on Fernandina they are brick red and dull greenish. Another difference between the iguanas is size, which is different depending on the island the individual iguana inhabits. The iguanas living on the islands of Fernandina and Isabela (named for the famous rulers of Spain) are the largest found anywhere in the Galápagos. On the other end of the spectrum, the smallest iguanas are found on the island on Genovesa. Adult males are approximately 1.3 m long, females 0.6 m, males weigh up to 1.5 kg. On land, the marine iguana is rather a clumsy animal, but in the water it is a graceful swimmer, using its powerful tail to propel itself. As an exothermic animal, the marine iguana can spend only a limited time in the cold sea, where it dives for algae. However, by swimming only in the shallow waters around the island they are able to survive single dives of up to half an hour at depths of more than 15 m. After these dives, they return to their territory to bask in the sun and warm up again. When cold, the iguana is unable to move effectively, making them vulnerable to predation, so they become highly aggressive before heating up (since they are unable to run away they try to bite attackers in this state). During the breeding season, males become highly territorial. The males assemble large groups of females to mate with, and guard them against other male iguanas. However, at other times the species is only aggressive when cold. Marine iguanas have also been found to change their size to adapt to varying food conditions. During El Niño conditions when the algae that the iguanas feed on was scarce for a period of two years, some were found to decrease their length by as much as 20%. When food conditions returned to normal, the iguanas returned to their pre-famine size. It is speculated that the bones of the iguanas actually shorten as a shrinkage of connective tissue could only account for a 10% length change. Researchers theorize that land and marine iguanas evolved from a common ancestor since arriving on the islands from South America, presumably by driftwood. It is thought that the ancestral species inhabited a part of the volcanic archipelago that is now submerged. A second school of thought holds that the Marine iguana may have evolved from a now extinct family of seagoing reptiles. Its generic name, Amblyrhynchus, is a combination of two Greek words, Ambly- from Amblus meaning "blunt" and rhynchus meaning "snout". Its specific name is the Latin word cristatus meaning "crested," and refers to the low crest of spines along the animal's back. Amblyrhynchus is a monotypic genus in that Amblyrhynchus cristatus is the only species which belongs to it at this point in time. This species is completely protected under the laws of Ecuador. El Niño effects cause periodic declines in population, with high mortality, and the marine iguana is threatened by predation by exotic species. The total population size is unknown, but is, according to IUCN, at least 50,000, and estimates from the Charles Darwin Research Station are in the hundreds of thousands. The marine iguanas have not evolved to combat newer predators. Therefore, cats and dogs eat both the young iguanas and dogs will kill adults due to the iguanas' slow reflex times and tameness. Dogs are especially common around human settlements and can cause tremendous predation. Cats are also common in towns, but they also occur in numbers in remote areas where they take a toll on iguanas.
Only in Galagapagos! The sign says, "Beware, Iguana's crossing"!
Isabella
Shaped like a sea horse, Isabela is the largest of the the islands in the Galapagos, more than 4 times larger than Santa Cruz the next largest. Isabela is 80 miles (100 km) in length and though it is remarkably beautiful it is not one of the most visited islands in the chain. Its visitor sites are far apart making them accessible only to faster boats or those with longer itineraries. One of the youngest islands, Isabela is located on the western edge of the archipelago near the Galapagos hot spot. At approximately 1 million years old, the island was formed by the merger of 6 shield volcanoes - Alcedo, Cerro Azul, Darwin, Ecuador, Sierra Negra and Wolf. Five of the six volcanoes are still active (the exception is Ecuador) making it one of the most volcanically active places on earth. Visitors cruising past Elizabeth Bay on the west coast can see evidence of this activity in the fumaroles rising from Volcan Chico on Sierra Negra. Two of Isabela's volcanoes lie directly on the equator - Ecuador and Volcan Wolf. Volcan Wolf is the youngest of Isabela's volcanoes and at 5,600ft (1707 m) the highest point in the Galapagos. Isabela is known for its geology, providing visitors with excellent examples of the geologic occurrences that have created the Galapagos Islands including uplifts at Urbina Bay and the Bolivar Channel, Tuft cones at Tagus Cove, and Pulmace on Alcedo. Isabela is also interesting for its flora and fauna. The young island does not follow the vegetation zones of the other islands. The relatively new lava fields and surrounding soils have not developed the sufficient nutrients required to support the varied life zones found on other islands. Another obvious difference occurs on Volcan Wolf and Cerro Azul, these volcanoes loft above the cloud cover and are arid on top. Isabela's rich animal, bird, and marine life is beyond compare. Isabela is home to more wild tortoises than all the other islands. Isabela's large size and notable topography created barriers for the slow moving tortoises; apparently the creatures were unable to cross lava flows and other obstacles, causing several different sub-species of tortoise to develop. Today tortoises roam free in the calderas of Alcedo, Wolf, Cerro Azul, Darwin and Sierra Negra. Alcedo Tortoises spend most of their life wallowing in the mud at the volcano crater. The mud offers moisture, insulation and protects their exposed flesh from mosquitoes, ticks and other insects. The giant tortoises have a mediocre heat control system requiring them to seek the coolness of the mud during the heat of the day and the extra insulation during the cool of the night. On the west coast of Isabela the nutrient rich Cromwell Current upwelling creating a feeding ground for fish, whales, dolphin and birds. These waters have long been known as the best place to see whales in the Galapagos. Some 16 species of whales have been identified in the area including humpbacks, sperms, sei, minkes and orcas. During the 19th century whalers hunted in these waters until the giant creatures were near extinction. The steep cliffs of Tagus Cove bare the names of many of the whaling ships and whalers which hunted in these waters. Birders will be delighted with the offerings of Isabela. Galapagos Penguins and flightless cormorants also feed from the Cromwell Current upwelling. These endemic birds nest along the coast of Isabela and neighboring Fernandina. The mangrove finch, Galapagos Hawk, brown pelican, pink flamingo and blue heron are among the birds who make their home on Isabela. A colorful part to any tour located on the western shore of Isabela, Punta Moreno is often the first or last stopping point on the island (depending on the direction the boat is heading). Punta Moreno is a place where the forces of the Galapagos have joined to create a work of art. The tour starts with a panga ride along the beautiful rocky shores where Galapagos penguins and shore birds are frequently seen. After a dry landing the path traverses through jagged black lava rock. As the swirling black lava flow gave way to form craters, crystal tide pools formed-some surrounded by mangroves. This is a magnet for small blue lagoons, pink flamingos, blue herons, and Bahama pintail ducks. Brown pelican can be seen nesting in the green leaves of the mangroves. You can walk to the edge of the lava to look straight down on these pools including the occasional green sea turtle, white-tipped shark and puffer fish. This idyllic setting has suffered from the presence of introduced species. Feral dogs in the area are known to attack sea Lions and marine iguanas.
Galapagos Islands
The Galápagos Islands (official name: Archipiélago de Colón; other Spanish names: Islas de Colón or Islas Galápagos) are an archipelago of volcanic islands distributed around the equator in the Pacific Ocean, some 900 km west of Ecuador. It is a UNESCO World Heritage site: wildlife is its most notable feature. Because of the only very recent arrival of man the majority of the wildlife has no fear of humans and will allow visitors to walk right up them, often having to step over Iguanas or Sea Lions.The Galápagos islands and its surrounding waters are part of a province, a national park, and a biological marine reserve. The principal language on the islands is Spanish. The islands have a population of around 40,000, which is a 40-fold expansion in 50 years. The islands are geologically young and famed for their vast number of endemic species, which were studied by Charles Darwin during the voyage of the Beagle. His observations and collections contributed to the inception of Darwin's theory of evolution by natural selection.
Galapagos Islands-694
One of the massive Marine Iguanas on Isabella
Marine Iguana
The Marine Iguana (Amblyrhynchus cristatus) is an iguana found only on the Galapagos Islands that has the ability, unique among modern lizards, to live and forage in the sea. It has spread to all the islands in the archipelago, and is sometimes called the Galapagos Marine Iguana. It mainly lives on the rocky Galapagos shore, but can also be spotted in marshes and mangrove beaches. On his visit to the islands, Charles Darwin was revolted by the animals' appearance, writing “The black Lava rocks on the beach are frequented by large (2-3 ft), disgusting clumsy Lizards. They are as black as the porous rocks over which they crawl & seek their prey from the Sea. I call them 'imps of darkness'. They assuredly well become the land they inhabit.” In fact, Amblyrhynchus cristatus is not always black; the young have a lighter coloured dorsal stripe, and some adult specimens are grey. The reason for the sombre tones is that the species must rapidly absorb heat to minimize the period of lethargy after emerging from the water. They feed almost exclusively on marine algae, expelling the excess salt from nasal glands while basking in the sun, and the coating of salt can make their faces appear white. In adult males, coloration varies with the season. Breeding-season adult males on the southern islands are the most colorful and will acquire reddish and teal-green colors, while on Santa Cruz they are brick red and black, and on Fernandina they are brick red and dull greenish. Another difference between the iguanas is size, which is different depending on the island the individual iguana inhabits. The iguanas living on the islands of Fernandina and Isabela (named for the famous rulers of Spain) are the largest found anywhere in the Galápagos. On the other end of the spectrum, the smallest iguanas are found on the island on Genovesa. Adult males are approximately 1.3 m long, females 0.6 m, males weigh up to 1.5 kg. On land, the marine iguana is rather a clumsy animal, but in the water it is a graceful swimmer, using its powerful tail to propel itself. As an exothermic animal, the marine iguana can spend only a limited time in the cold sea, where it dives for algae. However, by swimming only in the shallow waters around the island they are able to survive single dives of up to half an hour at depths of more than 15 m. After these dives, they return to their territory to bask in the sun and warm up again. When cold, the iguana is unable to move effectively, making them vulnerable to predation, so they become highly aggressive before heating up (since they are unable to run away they try to bite attackers in this state). During the breeding season, males become highly territorial. The males assemble large groups of females to mate with, and guard them against other male iguanas. However, at other times the species is only aggressive when cold. Marine iguanas have also been found to change their size to adapt to varying food conditions. During El Niño conditions when the algae that the iguanas feed on was scarce for a period of two years, some were found to decrease their length by as much as 20%. When food conditions returned to normal, the iguanas returned to their pre-famine size. It is speculated that the bones of the iguanas actually shorten as a shrinkage of connective tissue could only account for a 10% length change. Researchers theorize that land and marine iguanas evolved from a common ancestor since arriving on the islands from South America, presumably by driftwood. It is thought that the ancestral species inhabited a part of the volcanic archipelago that is now submerged. A second school of thought holds that the Marine iguana may have evolved from a now extinct family of seagoing reptiles. Its generic name, Amblyrhynchus, is a combination of two Greek words, Ambly- from Amblus meaning "blunt" and rhynchus meaning "snout". Its specific name is the Latin word cristatus meaning "crested," and refers to the low crest of spines along the animal's back. Amblyrhynchus is a monotypic genus in that Amblyrhynchus cristatus is the only species which belongs to it at this point in time. This species is completely protected under the laws of Ecuador. El Niño effects cause periodic declines in population, with high mortality, and the marine iguana is threatened by predation by exotic species. The total population size is unknown, but is, according to IUCN, at least 50,000, and estimates from the Charles Darwin Research Station are in the hundreds of thousands. The marine iguanas have not evolved to combat newer predators. Therefore, cats and dogs eat both the young iguanas and dogs will kill adults due to the iguanas' slow reflex times and tameness. Dogs are especially common around human settlements and can cause tremendous predation. Cats are also common in towns, but they also occur in numbers in remote areas where they take a toll on iguanas.
Only in Galagapagos! The sign says, "Beware, Iguana's crossing"!
Isabella
Shaped like a sea horse, Isabela is the largest of the the islands in the Galapagos, more than 4 times larger than Santa Cruz the next largest. Isabela is 80 miles (100 km) in length and though it is remarkably beautiful it is not one of the most visited islands in the chain. Its visitor sites are far apart making them accessible only to faster boats or those with longer itineraries. One of the youngest islands, Isabela is located on the western edge of the archipelago near the Galapagos hot spot. At approximately 1 million years old, the island was formed by the merger of 6 shield volcanoes - Alcedo, Cerro Azul, Darwin, Ecuador, Sierra Negra and Wolf. Five of the six volcanoes are still active (the exception is Ecuador) making it one of the most volcanically active places on earth. Visitors cruising past Elizabeth Bay on the west coast can see evidence of this activity in the fumaroles rising from Volcan Chico on Sierra Negra. Two of Isabela's volcanoes lie directly on the equator - Ecuador and Volcan Wolf. Volcan Wolf is the youngest of Isabela's volcanoes and at 5,600ft (1707 m) the highest point in the Galapagos. Isabela is known for its geology, providing visitors with excellent examples of the geologic occurrences that have created the Galapagos Islands including uplifts at Urbina Bay and the Bolivar Channel, Tuft cones at Tagus Cove, and Pulmace on Alcedo. Isabela is also interesting for its flora and fauna. The young island does not follow the vegetation zones of the other islands. The relatively new lava fields and surrounding soils have not developed the sufficient nutrients required to support the varied life zones found on other islands. Another obvious difference occurs on Volcan Wolf and Cerro Azul, these volcanoes loft above the cloud cover and are arid on top. Isabela's rich animal, bird, and marine life is beyond compare. Isabela is home to more wild tortoises than all the other islands. Isabela's large size and notable topography created barriers for the slow moving tortoises; apparently the creatures were unable to cross lava flows and other obstacles, causing several different sub-species of tortoise to develop. Today tortoises roam free in the calderas of Alcedo, Wolf, Cerro Azul, Darwin and Sierra Negra. Alcedo Tortoises spend most of their life wallowing in the mud at the volcano crater. The mud offers moisture, insulation and protects their exposed flesh from mosquitoes, ticks and other insects. The giant tortoises have a mediocre heat control system requiring them to seek the coolness of the mud during the heat of the day and the extra insulation during the cool of the night. On the west coast of Isabela the nutrient rich Cromwell Current upwelling creating a feeding ground for fish, whales, dolphin and birds. These waters have long been known as the best place to see whales in the Galapagos. Some 16 species of whales have been identified in the area including humpbacks, sperms, sei, minkes and orcas. During the 19th century whalers hunted in these waters until the giant creatures were near extinction. The steep cliffs of Tagus Cove bare the names of many of the whaling ships and whalers which hunted in these waters. Birders will be delighted with the offerings of Isabela. Galapagos Penguins and flightless cormorants also feed from the Cromwell Current upwelling. These endemic birds nest along the coast of Isabela and neighboring Fernandina. The mangrove finch, Galapagos Hawk, brown pelican, pink flamingo and blue heron are among the birds who make their home on Isabela. A colorful part to any tour located on the western shore of Isabela, Punta Moreno is often the first or last stopping point on the island (depending on the direction the boat is heading). Punta Moreno is a place where the forces of the Galapagos have joined to create a work of art. The tour starts with a panga ride along the beautiful rocky shores where Galapagos penguins and shore birds are frequently seen. After a dry landing the path traverses through jagged black lava rock. As the swirling black lava flow gave way to form craters, crystal tide pools formed-some surrounded by mangroves. This is a magnet for small blue lagoons, pink flamingos, blue herons, and Bahama pintail ducks. Brown pelican can be seen nesting in the green leaves of the mangroves. You can walk to the edge of the lava to look straight down on these pools including the occasional green sea turtle, white-tipped shark and puffer fish. This idyllic setting has suffered from the presence of introduced species. Feral dogs in the area are known to attack sea Lions and marine iguanas.
Galapagos Islands
The Galápagos Islands (official name: Archipiélago de Colón; other Spanish names: Islas de Colón or Islas Galápagos) are an archipelago of volcanic islands distributed around the equator in the Pacific Ocean, some 900 km west of Ecuador. It is a UNESCO World Heritage site: wildlife is its most notable feature. Because of the only very recent arrival of man the majority of the wildlife has no fear of humans and will allow visitors to walk right up them, often having to step over Iguanas or Sea Lions.The Galápagos islands and its surrounding waters are part of a province, a national park, and a biological marine reserve. The principal language on the islands is Spanish. The islands have a population of around 40,000, which is a 40-fold expansion in 50 years. The islands are geologically young and famed for their vast number of endemic species, which were studied by Charles Darwin during the voyage of the Beagle. His observations and collections contributed to the inception of Darwin's theory of evolution by natural selection.