Wild Florida: The Great Egret

The Great Egret is one of Florida’s more common waterbirds, and also one of the largest.

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There are a number of varieties of Great Egret distributed in semi-tropical and temperate areas around the world. The European variety, Ardea alba alba, is also sometimes known (incorrectly) as the White Heron. The subspecies A. alba modesta, found in south and east Asia, is the largest, and some authorities consider it to be a separate species. In Africa the subspecies is A. alba melanorhynchos.

The American subspecies is Ardea alba egretta. Standing about three feet tall and with a wingspan over four feet, it is one of the largest birds in North America. Like the other subspecies, the plumage is pure white. In southern Florida, the Great Egret can be confused with the pure-white color morph of the Great Blue Heron, but the Egret can be distinguished by its yellow beak and black legs and feet, and its longer and wider wings in flight. Egrets are mostly silent, except for a weak “skronk” call when disturbed.

In Florida, the Egret is a year-round resident. Other populations can range as far north as Canada, with western groups migrating to Mexico for the winter, and easterns wintering in Central or South America. Like all wading waterbirds, they can be found in virtually any permanent body of water, including ponds, lakes, rivers, salt marshes, and seashores.

Typically, Egrets spend most of their time in shallow water, hunting for fish, frogs, and aquatic invertebrates. They wade along slowly, spearing prey with their long bills. Egrets have been observed holding out their wings to create a spot of shade in the water to attract fish. I have also seen them investigating shrubbery onshore for Anole lizards, which they eagerly snap up. They will also eat baby alligators, mice, and snakes; there have even been reports of Great Egrets nabbing and eating smaller birds.

The males and females look the same, though the males tend to be slightly larger. During the spring breeding season, both sexes develop long showy plumes (known as “aigrettes”) as a mating display. During the later part of the 19th century, these lacy plumes were highly prized for decorating women’s hats, and the Egrets, along with many other bird species, were hunted nearly to extinction. They have since made a comeback, and are now a common sight in Florida.

Egrets typically are ready to breed at around two or three years of age. The males will choose a spot for a nest, defend it from other males, and attract a female with a mating display consisting of neck-stretching and bill-pointing. Unlike some wading birds, the nests are not re-used from year-to-year, and the birds select a new breeding partner every year.

Once the pair have mated, they begin constructing a nest in a shrub or tree. Like many other waterbirds, Egrets prefer to nest on islands, where alligators protect them from terrestrial predators like snakes and raccoons. The rookeries are large and can also contain other species like Ibis, Little Blue Herons, and Cattle Egrets.The nest is a large flat platform made from sticks, sometimes a yard across, and lined with moss and leaves. The female lays four or five eggs which hatch in about three and a half weeks. The nestling birds have pink bills and are coverd with downy fuzz. After about three weeks, they are able to climb out of the nest and clamber around in nearby branches, and after another week or two are ready to fledge. With their icepick bills, the older nestlings can aslo defend themselves from marauding predators.

In years when food is plentiful, all of the chicks usually survive to leave the nest; in years when food is scarce, the largest chick will usually dominate the others, either killing them outright or causing them to starve. In good times, the Florida populations will often produce two clutches per year. Tagged adult Egrets have lived as long as 20 years.

The National Audubon Society has adopted the Great Egret as its logo, since the group was originally formed to lobby for laws banning the use of bird feathers in hats.

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