Western Cattle Egret
Western Cattle Egret
Bubulcus ibis
At a Glance
The remarkable range expansion of the Cattle Egret represents one of the great avian success stories. Unknown in North America prior to 1952, it is now abundant over much of the continent. It spread from Africa to northeastern South America in the 1870s and 1880s; more recently it has colonized Australasian region. Unlike other herons and egrets, this species typically feeds in dry fields, often following cattle (or other animals) and waiting for them to flush insects into view.
All bird guide text and rangemaps adapted from by Kenn Kaufman漏 1996, used by permission of Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Category
Herons, Egrets, Bitterns, Long-legged Waders
IUCN Status
Least Concern
Habitat
Coasts and Shorelines, Fields, Meadows, and Grasslands, Freshwater Wetlands, Saltwater Wetlands
Region
California, Eastern Canada, Florida, Great Lakes, Mid Atlantic, New England, Northwest, Plains, Rocky Mountains, Southeast, Southwest, Texas, Western Canada
Behavior
Direct Flight
Population
48.000.000
Range & Identification
Migration & Range Maps
Strongly migratory. Birds from northern breeding areas in North America may winter to West Indies, Central America, northern South America. Common at all seasons in Florida, Gulf Coast, parts of southwest. Dispersal of young birds may cover long distances, even thousands of miles, in random directions; this behavior probably aided the species' colonization of much of the world.
Description
20" (51 cm). More compact and chunkier than other white herons. Yellow bill is noticeably short. Legs vary from yellow or pink in breeding season to dusky or black in winter. In breeding plumage, shows patches of buff feathers.
Size
About the size of a Crow, About the size of a Mallard or Herring Gull
Color
Black, Orange, Tan, White, Yellow
Wing Shape
Broad, Fingered, Pointed, Rounded
Tail Shape
Short
Songs and Calls
Hoarse croaks
Call Pattern
Flat, Simple
Call Type
Croak/Quack, Raucous
Habitat
Farms, marshes, highway edges; often associates with cattle. Widespread in any kind of open country, including pastures, plowed fields, lawns, roadsides. Also in aquatic habitats, including flooded fields, marshes. Nests in trees or shrubs, in colonies with other herons and egrets.
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Behavior
Eggs
3-4, sometimes 1-9. Pale blue. Incubation is by both sexes, 21-26 days.
Young
Both parents feed young, by regurgitation. Young begin to climb about near nest after 15-20 days, begin to fly at 25-30 days, and become independent at about 45 days.
Feeding Behavior
Usually forages in flocks in dry fields, very often in association with grazing animals -- usually cattle or horses in North America, but on other continents also elephants, camels, zebras, deer, many others. Insects are flushed from grass by animals, caught by egrets. At times, Cattle Egrets will follow tractors or even lawnmowers for the same result.
Diet
Mostly insects. When associating with grazing animals in fields, diet is mostly large insects, especially grasshoppers, crickets, flies; also frogs, spiders, moths. Elsewhere may feed on crayfish, earthworms, snakes, nestling birds, eggs, sometimes fish. May scavenge for edible refuse in dumps.
Nesting
Usually first breeds at age of 2-3 years. Breeds in colonies, usually joining colonies already established by other herons and egrets despite very different feeding habitat. Male establishes pairing territory (in or near colony) and displays there to attract mate. Displays include stretching neck and raising plumes while swaying from side to side, making short flights with exaggerated deep wingbeats. Nest: Site is in colony, in trees or shrubs, often in swamps or on island. Nest (built mostly by female, with materials mostly brought by male) is platform or shallow bowl of sticks, often with green leafy twigs added.
Climate Vulnerability
Conservation Status
North American population may still be increasing, although not as rapidly as in earlier years. In northern heronries, may compete with native species for nest sites; thought to have crowded out native herons or egrets in some instances. In general, however, little negative impact on any native species.
Climate Threats Facing the Western Cattle Egret
Choose a temperature scenario below to see which threats will affect this species as warming increases. The same climate change-driven threats that put birds at risk will affect other wildlife and people, too.