Anhinga

Few sights say "southern swamp" like an Anhinga perched on a snag with its wings spread wide, drying in the sun like a feathered crucifix. This large, slim waterbird of warm American wetlands is equally famous for the way it swims: body fully submerged, with only a slender, kinked neck and dagger-shaped head cutting the surface. That eerie, serpent-like profile earned it the nickname snakebird, and it can genuinely startle first-time observers who mistake it for a snake gliding across a cypress pond.

The trick behind both behaviors is the same. Unlike ducks, the Anhinga has feathers that soak through in water. Wettable plumage kills buoyancy, letting the bird sink silently and stalk fish underwater like a slow-motion torpedo, but it also means the Anhinga must haul out and sunbathe to dry off and warm up. Closely related to cormorants yet distinct from them, it stabs prey with a sharp, pointed bill rather than grabbing it. It is also a surprisingly graceful flier, soaring high on thermals with its long tail fanned like a turkey's, which explains its old Florida name, the water turkey.

The Anhinga is a large but very slender waterbird with an extremely long, thin neck, a small head that barely widens beyond the neck, a straight stiletto bill, and a long, broad, fan-shaped tail. Perched, it looks lanky and reptilian; in flight it forms a distinctive flying cross, with neck fully extended and tail spread. The classic confirmation marks are the silvery-white streaks and panels across the upper wings and back, visible on both sexes, and the pointed (never hooked) bill.

Male vs. female

Anhingas are one of the easier waterbirds to sex at a glance. The male is almost entirely glossy black with a greenish sheen, set off by bold silver-white streaks and spangles across the upper wings and back. In breeding condition he adds wispy pale plumes on the head and neck, and the bare skin around the eye can flush vivid blue-green during courtship.

The female keeps the black body and silvery wing pattern but wears a warm buff to tan hood over the head, neck and chest, which meets the dark belly in a clean, crisp line. That two-toned look is diagnostic: no female cormorant in the Anhinga's range shows a pale tan neck contrasting with a black body. Immature birds resemble females but are browner and duller overall.

Juveniles

Juvenile Anhingas look like washed-out versions of the adult female. The head, neck and breast are pale buffy-brown, the body is dull brownish-black rather than glossy, and the silvery wing markings are muted or patchy. Young males gradually darken over their first couple of years, often showing a messy mix of tan and black on the neck as adult plumage comes in. In the nest, chicks are covered in pale buffy down and are fed by regurgitation, sometimes reaching deep into a parent's throat. Older nestlings that feel threatened will drop out of the nest into the water below and clamber back up afterward, a startling but normal escape trick.

Away from the breeding colony the Anhinga is mostly a silent bird, which fits its stealthy hunting style. What voice it has is mechanical rather than musical: the commonest sound is a rapid, dry rattle or clicking chatter, a bit like a distant sewing machine or a stick dragged along a fence. Birds also give low croaks, grunts and buzzy notes, mainly around the nest.

Listen for the clicking rattle when a bird lands at a roost or when pairs interact at the colony, and during courtship displays, when males wave their wings, bow and rattle from a chosen nest site. There is no true song and no traditional mnemonic; if you hear a long rattling chatter from a dead snag over a swamp, look up and you will often find the bird sunning above you.

The Anhinga is a bird of the warm Americas. In the United States it is most common in Florida, coastal Georgia and South Carolina, and along the Gulf Coast through Louisiana and Texas, extending up big southern river systems such as the lower Mississippi. From there its range runs through Mexico and Central America and across much of South America east of the Andes, south to roughly northern Argentina. Birds from the northern edge of the range withdraw southward in winter, while populations in Florida and the tropics are largely year-round residents.

Habitat matters more than geography for finding one: Anhingas want warm, calm, sheltered fresh or brackish water with fish and with perches. Cypress swamps, slow blackwater rivers, marshes, oxbows, willow-lined ponds, lagoons and mangrove edges are all classic haunts. They avoid cold water and open surf, which is one reason they stay southern while cormorants range far to the north. On sunny mornings, scan dead snags and low branches over the water for the unmistakable spread-winged silhouette.

The Anhinga is a fish specialist with a hunting method all its own. Rather than chasing prey at speed like a cormorant, it sinks quietly and stalks through submerged vegetation, neck coiled back in an S. A hinge-like mechanism in the neck vertebrae lets that coil release like a spring, driving the partly opened bill forward to impale a fish, often clean through the body. Slower-moving species such as sunfish, catfish and other pond fish make up most of the catch.

Once a fish is speared, the bird surfaces, shakes or pries it off the bill, flips it into the air and swallows it head-first so the fins fold flat. Fish that are stuck fast may be hammered against a branch or rock first. Beyond fish, Anhingas also take crayfish and other crustaceans, aquatic insects, tadpoles and frogs, and occasionally small water snakes or young turtles.

Anhingas breed in colonies, usually mixed in with herons, egrets, ibises and cormorants at wading-bird rookeries. Nests are built in trees or shrubs standing over or beside water, often in cypress, willow or mangrove, typically a few meters above the surface. The male chooses the site and displays there with wing-waving and bowing; he then delivers most of the sticks while the female builds, shaping a bulky platform lined with fresh green leaves and twigs. Pairs sometimes refurbish an old nest, including nests originally built by egrets.

The female typically lays two to five chalky, pale bluish eggs, laid a day or more apart, so the chicks hatch at intervals and differ in size. Both parents share incubation, which takes roughly four weeks, and both feed the young by regurgitation. Chicks clamber about the nest tree using their feet, bill and stubby wings well before they can fly, and fledge at around six weeks, usually staying near the colony a while longer. One brood per year is the norm.

The Anhinga is not a backyard bird and will not visit feeders, so attracting one is really about going where it lives. The good news is that in the right wetlands it is remarkably easy to see, often perched in the open at close range and largely unbothered by people on boardwalks.

• Visit Everglades National Park in Florida, where the aptly named Anhinga Trail near the Royal Palm entrance offers point-blank views of hunting, sunning and nesting birds.
• Try other southeastern wetland refuges such as Corkscrew Swamp Sanctuary, Wakulla Springs, the Savannah River refuges, and Louisiana and Texas coastal swamps and bayous.
• Time your search for sunny mornings after cool nights, when birds haul out to dry and warm up in the classic spread-winged pose on snags over the water.
• Scan the water surface for a periscoping neck, a thin, kinked snake-like head and neck moving with no visible body is often an Anhinga rather than a snake.
• Check wading-bird rookeries in spring, Anhingas nest alongside herons and egrets, and courting males show off blue-green eye skin and silvery wing plumes.
• In the tropics, look along slow rivers, oxbow lakes and mangrove lagoons from Mexico to Argentina, often from a boat, where Anhingas perch low over the water.

• Double-crested Cormorant: Hook-tipped orange-yellow bill, shorter rounded tail and thicker neck; swims higher in the water and grabs rather than spears fish, with no silvery wing streaks
• Neotropic Cormorant: Smaller, all-dark cormorant sharing much of the Anhinga's range; long-tailed for a cormorant but still hook-billed, stockier and plain-winged
• Oriental Darter: Old World counterpart with nearly identical snakebird shape and wing-drying habit; found in Asia, so range alone separates the two