Where does the great blue heron nest and breed?
Most great blue herons breed in localized colonies (called rookeries or heronries) of sometimes hundreds of nesting pairs. Colonies are located at isolated sites where ground predator and human access is limited, such as woodland swamps and small islands. • The male heron builds a nest of sticks and twigs high in the canopy of a tree, safe from predators. • Great blue herons may begin breeding activities as early as February. New breeders may continue to arrive at the colonies well into May. • The peak of egg-laying season occurs from mid-March to mid-June. Clutch size varies from three to seven eggs, with an average of four eggs. • Both parents incubate the eggs for about 28 days, and the peak of hatching takes place from mid-April to mid-July. • Though they may have several eggs, great blue heron pairs usually only raise one or two young; the others starve after hatching. • Fledging occurs at about 60 days. Immature great blue herons have a solid black crown without plumes. Other fac
