Ardea alba

Taxonomy

Member of the heron family, Ardeidae. While traditionally classified with the storks in the Ciconiiformes, the Ardeidae are actually more closely related to pelicans and belong in the Pelecaniformes instead. Unlike typical egrets, the Great Egret does not belong to the genus Egretta but is placed with the great herons in the Ardea.

Physical Description

Tall, long-legged wading birds with long, S-curved necks and long, sharp bills. In flight, the long neck is tucked in and the legs extend far beyond the tip of the short tail. Great Egrets have all white feathers. Their bills are yellowish-orange, and they have black legs.

Ecology and HabitatThe great egret is partially migratory, with northern hemisphere birds moving south from areas with colder winters. It adapts well to human presence and can be seen near wetlands and bodies of water in urban and suburban areas. Great egrets are found both in freshwater and saltwater habitats. They are colonial nesters who typically place stick nests high in trees, often on islands that are isolated from mammalian predators. Great egrets are native to the Santa Barbara area.

Diet and Behavior

Feeds in shallow water or drier areas, mainly on fish, frogs, small mammals, and occasionally small reptiles and insects. It stands still and allows its prey to come within its reach, and then spears them with its long beak. Though it often waits motionless for prey, it also may slowly stalk its victim.

Great Egrets form monogamous pairs each breeding season. Early in the season adults grow long plumes on their backs, which they use for courtship displays. Male egrets perform most of the displays, which can involve preening the wings, ducking the head, holding and shaking twigs in the bill, and stretching the neck. Nestlings compete fiercely with each other, and dominant chicks sometimes end up stabbing the youngest siblings to death.

Population Trends

The great egret is generally a very successful species with a large and expanding range. According to the North American Breeding Bird Survey, populations increased across most of their range from 1966 to 2010. In North America, large numbers of great egrets were killed around the end of the 19th century, as their plumes were used to decorate hats. Numbers have since greatly recovered as a result of conservation measures, and because of this the great egret became the symbol of the Audubon society. Its range has expanded as far north as southern Canada, although in some parts of Canada and the southern United States, its numbers have declined due to habitat loss. However, relative to other egrets and herons the Great Egret has been very successful in dealing with reduced habitats.

Field Notes

Multiple great egrets were seen on two trips through Devereaux Lagoon and the Elwood Mesa. In both cases an egret was seen on a sandbar in the middle of a snaking river in the mostly dry lagoon flat. In one sighting at dusk, the egret stood completely still for about five minutes before flying away. In the other, the egret slowly stalked forward before quickly spearing into the water. Earlier in the afternoon, three egrets were seen together in a grassy field up on the mesa

Share this Story