Reference: Anhinga

Anhingas (Anhinga anhinga) are strange birds. Also called snakebirds, devil birds, and wa-ter turkeys, anhingas are waterbirds without waterproof feathers and bones so dense that their bodies sink when they swim. Their long, kinked, S-shaped necks flow into long, daggerlike bills, with only glaring red eyes and a small bend in the silhou-ette giving a clue that the head is there. They look like prehistoric remnants of an earlier age, and they are—anhinga fossils dating back one million years have been found.

From a distance, anhingas look a little like their cousins the cormorants, but there are differences. Cormorants like to be together, often gathering in flocks with hundreds of birds; anhingas like their alone time and tend to squabble with neighbors. Cormorants arch and dive to chase their prey through the water, grabbing and holding it with the sharp hook at the tip of their bills. Anhingas, on the other hand, quietly slip below the surface and, with tail and wings spread underwater, look for fish that they can sneak up on and spear with their sharp bills.

After an anhinga spears a fish—usually bream or bass—it swims to the surface and flings it into the air like a juggler, catching it headfirst and swallow-ing it whole.

These birds come back from every swim wet and bedraggled. Ducks, geese, and swans have water-proof feathers, but anhingas are drenched to the skin whenever they hit the water. They need to dry off and quickly warm their bodies, so they climb onto a nearby branch, turn their backs to the sun, lift their heads, spread their wings, and let their glossy black feathers absorb the warmth.

Anhingas live in the tropical areas of the Amer-icas, so they can afford to stretch out their breed-ing season. While other birds race north to quickly raise a family or two, anhingas stay home nesting at their leisure between February and July. Nestlings have even been found as late as December.

Like other birds, they give telltale signs that their breeding season has started. The lores and fleshy areas around their ruby-red eyes turn green on the females and brilliant turquoise on the males. The birds perform ritual displays, looking to the sky and slowly turning their heads back and forth as if surveying their realm. Males go a step further by crouching, curving their backs downward, point-ing their heads and necks to the sky, and spread-ing their tails over their backs. Then, they reverse, arching their backs and looking down. It’s like yoga for birds. They shake their wings, rattle branches, stab at intruders, and generally make a ruckus to let the world know that their spot is taken.

Males are also the nest builders. The male anhin-ga starts with a few sticks placed on a good-looking fork on a branch or near the trunk of a tree and keeps adding until the nest is complete. Anhin-gas nest in colonies with herons, egrets, and other anhingas—a notorious crowd known for stealing nesting materials and even taking over other birds’ nests. So while the male brings sticks, the hen stays at the nest, protecting it from the neighbors. She won’t leave again until after her clutch of four eggs is complete.

Once the eggs are laid, the parents share the in-cubation duties. They patiently keep the eggs warm and protected for almost a month before they hatch. The eggs are laid up to four days apart and incubat-ed from day one, so they hatch at different times, making a nest of different-sized nestlings.

The hatchlings are pink, naked, and blind and can do little for the first few days after hatching. They grow rapidly on a diet of regurgitated fish, and when they are two weeks old, they can jump down to the water if they are disturbed (although they pre-fer not to) and then climb back to the nest. At three weeks, they are out of the nest and huddling in the branches of the colony. Their first clumsy flights take place around six weeks of age.

Their flying skills quickly improve. Even though anhingas sink in the water, they are master fliers that soar with eagles, hawks, and turkey vultures. Occasionally, one adventurous bird gets curious about the bigger world and soars to distant lands. Anhingas have been seen in places like Nebraska, Michigan, and Ontario—but the sun isn’t as strong in these northern lands, and when their feathers are wet, they need a warm place to relax. As a result, the birds always come back to the humid, wet, and warm lands that they call home.

It’s breeding season! This male displays the telltale breeding plumage and turquoise coloring around the eyes.

REFERENCE

Frederick, P.C. and D. Siegel-Causey (2020). Anhinga (Anhinga anhinga), version 1.0. In Birds of the World (A.F. Poole and F.B. Gill, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.anhing.01

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MEASUREMENTS (in mm)

	Culmen	Wing	Tarsus	Tail
Female	78.8	325	40.4	246
Male	83.4	329	41.1	245

*Adapted from Frederick, P.C., et. al.