Anhinga anhinga, Parque Nacional Yasuni, Ecuador (This Wild Wonderland)
The Anhinga is a striking figure both in and out of the water. The black and white contrast between the female bird’s body and neck is quite striking. In the water, their nickname “snakebird” becomes apparent, as they typically swim with just their head and neck protruding from the water. Another nickname, “darter,” refers to their style of hunting, where they quickly spear fish with their sharp bill.
The name Anhinga can refer to any of the four species in the Anhinga genus, which is the only genus in the family Anhingidae. Which of the four it is referring to can be determined by location, except on the island of New Guinea’s North coast, where Anhinga novaehollandiae and Anhinga melanogaster overlap. Anhinga melanogaster is also found in southern and south-eastern Asia and is classified as “Near Threatened.” Anhinga novaehollandiae is found throughout Australasia and Anhinga rufa is found in sub-Saharan Africa. Anhinga anhinga is found in coastal regions of the south-eastern United States, coastal Central and South America, and throughout the Amazon.
Anhinga Range Map
While anhingas are the only birds in their family, they are closely related to their sister taxon, Phalacrocoracidae, which contains cormorants and shags. Cormorants can be confused with anhingas but are distinguished by their blunter bills and shorter, narrower tails. Phalacrocoracidae and Anhingidae are both in the order Suliformes, which also contains gannets, boobies, and frigatebirds.
While appearing very similar and having many similar habits, cormorants and anhingas have very different ranges. Cormorants and shags are distributed widely, from the tropics to the Arctic and Antarctic. However, anhingas are all found in tropical and sub-tropical areas. This is due to a major difference that can’t be seen by most observers: anhingas lack an entire layer of insulating feathers compared to cormorants. This limits their range greatly, even for those that migrate (which are only those that live at the far north or far south of their range).
"...anhingas lack an entire layer of insulating feathers compared to cormorants"
Anhingas have no shortage of nicknames. In addition to “snakebird” and “darter,” the term “anhinga” originates from the Brazilian Tupi language meaning “devil bird.” In their drying pose, their resemblance to a male turkey has given them the nickname “water turkey” or “swamp turkey,” especially in the Southern US. However, the nicknames “snakebird” and “darter” reveal two of the group’s most interesting behaviors.
When swimming on the surface of the water, their bodies are completely submerged, making their necks look remarkably like snakes. When underwater, they swim with their bodies stretched out until they find a fish, at which point they dart towards it and impale it on their pointed bills. They then come to the surface and go to either the shallows or the shore, where they will move the fish to the tip of their bill and then flick their head so that the fish flies into the air and into their mouth. If it is a particularly large fish, they may come ashore and rub the fish against a tree trunk or other hard surface to get it off.
"When swimming on the surface of the water, their bodies are completely submerged, making their necks look remarkably like snakes."
Anhingas are monogamous-for-life and often reuse the same nest each year. A male will gather twigs and leaves that the female uses to construct a padded nest. These nests can be found in both saltwater and freshwater areas, often in colonies with other waterbirds such as herons, storks, and cormorants. The female will lay between two and six pale teal eggs. Both parents sit on the nest for around a month. The chicks are altricial and stay in the nest for about 3 weeks. However, if threatened, they will jump out of the nest and swim for safety. They will later climb back up and into the nest. After 3 weeks, they will begin venturing to nearby branches until they fledge at around 6 weeks, staying with their parents for several weeks after that. Most anhingas reach sexual maturity at about 2 years of age.
The anhingas are remarkable birds, possessing several exciting habits. They are also relatively unafraid of humans and will even bring their prey ashore when humans are nearby. This makes them a great species to observe and learn about, with potential for any number of new discoveries.