Knowledge unlocks a world of possibilities The Robinson Library

Home About The Library Navigation Help Sitemap Terms of Use Contact Information

  ScienceZoologyBirdsOrder Ciconiiformes


Great EgretGreat Egret

Ardea alba [ar' dE uh ahl' buh]

Description

The second largest member of the heron family (behind the great blue heron), the great egret stands just over 3 feet tall, has a wingspan of almost 5 five, and weighs just under 2 pounds.

Its feathers are entirely white, it has a long, sharp yellow bill, and long gray to black legs with non-webbed feet with very long toes.

In flight, the long s-shaped neck is tucked in and the legs extend far beyond the tip of the short tail.

Distribution and Habita

Great egrets are found in tropical and temperate wetlands on every continent except Antarctica.

They inhabit all kinds of wetlands, both inland and along the coast, including marshes, river margins, lakeshores, coastal swamps, lagoons, mudflats, and manmade impoundments and drainage ditches. They can also be found in more terrestrial habitats, such as agricultural fields. Nesting takes place mostly in waterside trees or shrubs, often on islands. Some populations migrate, often following routes along coastlines and major rivers.

Diet

The great egret stalks its prey by either standing still or walking slowly in shallow water and marshland, occasionally on land. When it spots its prey, it pulls its head and long neck back and then quickly stabs it with its long bill. In water, it preys on frogs, crayfish, snakes, fish, and insects. On land, it may take small mammals like moles and mice. The great egret usually feeds along in the early morning and evening hours.

mother egret in nest with chicksReproduction

At the beginning of the breeding season, great egrets develop long showy plumes, called aigrettes, which trail from their backs, and are prominently displayed during courtship. Their bills become orange-yellow, and the skin around their eyes changes from yellow to lime-green. Seasonally monogamous, the birds typically nest in large colonies, often with other species such as great blue herons or snowy egrets. In temperate zones they breed in spring or summer, depending on when food is most abundant; in the tropics, they can breed at any time of the year.

The nest is constructed by the male before he selects a mate. The nest itself is a platform of sticks or twigs up to 100 feet off the ground, often over water, usually in or near the top of a shrub or tree  Occasionally, the great egret will build its nest on dry ground near a marsh.

The female great egret lays three to five pale green-blue eggs. The eggs take about three to four weeks to incubate. Both parents incubate the eggs and feed the chicks. The chicks fledge in about six weeks. If the nest is on the ground, the chicks will walk around the nest before they fledge. Both the male and female aggressively defend the nesting territory. Aggression among nestlings is common and large chicks frequently kill their smaller siblings.

Conservation Status

In the nineteenth century great egrets were hunted nearly to extinction for their plumes, but conservation efforts and protection as a migratory species has allowed their numbers to increase dramatically. Although they are now fairly common, individual populations of great egrets are still vulnerable to habitat loss and pollution.

Scientific Classification

phylum Chordata
subphylum Vertebrata
class
Aves
order
Ciconiiformes
family Ardeidae
genus & species Ardea alba


All About Birds
http://www.allaboutbirds.org/guide/great_egret/id
National Audubon Society
http://birds.audubon.org/species/greegr
NatureWorks
http://www.nhptv.org/natureworks/greategret.htm


Great Blue Heron

Questions or comments about this page?

  The Robinson Library > Science > Zoology > Birds > Order Ciconiiformes

This page was last updated on September 22, 2016.

About This Site | Navigation Help | Sitemap | Terms of Use | Contact