Great Egret (Casmerodius albus)

Status: State Threatened (1979).

Occurrence: Fairly common migrant south; uncommon migrant central; rare migrant north. Uncommon summer resident west, south, and east; rare summer resident central. Egrets are found along the Mississippi River north to Pierce County and breeding has been confirmed north to Burnett County. Six colonies are located along the Mississippi River, and the largest colony is located at Horicon Marsh in Dodge County. A map outlining Pre-1977 and 1997 to Present Distribution is available.

Aid to ID: Plumage is white, bill is yellow, and legs and feet are glossy black. Largest of egrets that occur in Wisconsin.

Habitat: Found along streams, ponds, marshes, and mudflats; also inland lakes and wooded swamp areas.

Food Habits: Feed mainly on crayfish, shrimp, aquatic insects, frogs, fish, crabs, and snails. Occasionally feed on lizards, snakes, salamanders, mice, and moles.

Natural History:

Breeding: Clutch size: usually 3-4 pale blue-green eggs; laid from April to July. Incubation: 24 days. Young fledge at 42 days old.
Nest: Sticks and twigs or stems of marsh plants with little or no lining. Placed in medium-sized trees 20-40 feet up.

Management Considerations: Historically, colonies of thousands were reduced to small numbers in just a few years due to plume hunters. Wetland loss has resulted in less nesting habitat. Protection of large blocks of bottomland forests and large inland wetland complexes with riparian woods will provide suitable nesting habitat.