The tricolored heron (Egretta tricolor), formerly known as the Louisiana heron, is a small species of heron native to coastal parts of the Americas. The species is more solitary than other species of heron in the Americas and eats a diet consisting mostly of small fish.
Habitat, breeding, and distribution
Tricolored herons breed in swamps and other coastal habitats and nests in colonies, often with other herons, usually on platforms of sticks in trees or shrubs. In each clutch, three to seven eggs are typically laid. The tricolored heron is the second most coastal heron in the United States.
The species' range follows the northeastern United States, south along the coast, through the Gulf of Mexico and the Caribbean, to northern South America as far south as Brazil. In the Pacific region, it ranges from Peru to California, but it is only a nonbreeding visitor to the far north.
It was likely the most numerous heron in North America until the cattle egret arrived to the continent in the 1950s. While the species' population appears to be on the decline, it remains quite common. The bird is listed as "Threatened" by the Florida Fish and Wildlife Conservation Commission.
This species measures from 56 to 76 cm (22 to 30 in) long and has a typical wingspan of 96 cm (38 in). The slightly larger male heron weighs 415 g (14.6 oz) on average, while the female averages 334 g (11.8 oz). It is a medium-large, long-legged, long-necked heron with a long, pointed, yellowish or greyish bill with a black tip. Its legs and feet are dark. The plumage of the triclolored heron changes dramatically from its juvenile form to its adult form.
Adults have a blue-grey head, neck, back, and upper wings, with a white line along the neck. The belly is white. In breeding plumage, they have long, blue, filamentous plumes on their heads and necks, and buff ones on their backs.
The tricolored heron is more solitary when foraging than other North American herons. When it forages for its prey, it is typically belly-deep in water, alone or at the edge of a mixed flock. Kent (1986) found that the diets of tricolored herons in Florida consisted of 99.7% fish and prawns. While other members of Egretta may also eat crabs and opportunistically forage for terrestrial arthropods, the tricolored heron has been consistently observed to be almost exclusively piscivorous, primarily feeding on members of Poeciliidae.
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