APPEARANCE
Egrets are members of the Ardeidae family, which includes herons and bitterns. Large to medium-sized birds,
they are characterized by long legs and necks, and a long pointed bill. The plumage varies from white to
dark blue. Egrets are, on average, somewhat smaller than herons.
The great (or common) egret (Casmerodius albus) is the largest species, standing up to 40 inches, with a
wingspan of about 55 inches, (about 100 cm) whereas the cattle egret stands 20 inches high. The great egret's
plumage is entirely white, while the legs are black, and the bill yellow. Breeding birds have long plumes
(aigrettes) on the lower neck.
TAXONOMIC NOTE: This species is sometimes placed in the genus Ardea or Egretta. It is
known under various common names including American Egret (U.S.) and Great White Egret (Europe).
HABITAT AND DISTRIBUTION
The great egret is found across the world, in temperate and tropical regions. Its range is limited by high
elevations and latitudes where temperatures are too low to sustain populations. Like other aquatic birds, it
prefers areas of open water where prey is plentiful, such as slow-moving rivers, lakes and swampy areas.
FEEDING AND DIET
Most of the great egret's food consists of fish, amphibians, reptiles, birds, and small mammals and
invertebrates. While foraging, the bird moves slowly, standing still for minutes at a time. When a prey item
wanders by, the bird stabs it with a quick lunge of the bill. In South American lagoons, egrets main food are
shrimp, followed by guppies, crabs and insects.
BREEDING
Before the onset of the breeding season, the bird develops long plumes on the lower neck. During courtship
displays, the plumes that usually rest down against the chest are held up over the bird's back. Such
displays are typically conducted close by the nest.
Egrets nest in colonies with other herons, with the nest placed high in trees or shrubs, often above water.
The nest is a messy construction of sticks covered with greenery such as leaves and moss.
Three eggs are usually laid, of a pale greenish-blue. The female lays from one to six eggs.
Eggs incubate within 23 to 26 days. Hatchlings are covered with long white down and are
altricial, being able to hold the head up just after hatching.
CONSERVATION
The great egret populations are in fairly good shape. Given their wide geographic range and
adaptability, they can survive in a variety of habitats, although optimum habitat is being reduced with
widespread drainage of wetlands for agriculture and urban development. The loss of wetlands may render
local populations extinct, but no North American population is considered threatened.
In the last two centuries, North American populations dropped by 95 percent due to plume hunters who
sold the feathers to hat makers. The plumes were worth twice their weight in gold so its no wonder the
birds were almost wiped out. After such hats went out of fashion the birds were protected by law, the
populations recovered.
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