As an inhabitant almost exclusively of coastal lagoons of the Gulf Coast states, the Reddish Egret (Egretta rufescens) is North America’s rarest and least known ardeid. This species was nearly extirpated from the United States by plume hunters prior to 1900. Since then, populations have recovered, and U.S. populations currently total about 2,000 pairs; less is known about numbers in Mexico or the Caribbean. The species is dimorphic: the dark morph predominates in the United States and Mexico, with the white morph more common in the Bahamas and Greater Antilles. The Reddish Egret is remarkable for its extremely active foraging behavior, employing running, hopping, flying, and open-wing techniques to locate and pursue schools of small fish across barren shallow flats.
Medium-sized heron, length 70–80 cm; mass 700–850 g; two color morphs (white and dark). Dark morph may be confused with Tricolored (Egretta tricolor) or Little Blue (E. caerulea) herons, and white morph with Snowy Egret (E. thula) or immature Little Blue Heron. Reddish Egret relatively larger and taller than these species, also more prone to animated and erratic foraging (dashing, running, jumping, spreading wings), although above species may engage in such behavior on occasion. Immature Reddish Egret particularly nondescript, dark morph overall rather grayish (often brownish or rufous tinges on head, neck, and wings) with all-dark (slaty) bill and legs and whitish eyes (irides), which are distinctly paler than above species, which have more yellowish or dark (to reddish) irides.
During breeding season, adult Reddish Egret distinguished by bicolor pink bill with black tip, pink lores, slaty blue–gray legs, and shaggy plumes on rusty red head and neck that contrast with gray plumage of body. Tricolored Heron has white belly, long and slender neck and bill, and greenish to reddish legs. Little Blue Heron has bicolored bill, but base bluish; legs and feet greenish. White-morph Reddish Egret also has distinctive bicolored bill and is separated from smaller Snowy Egret by that species’ yellowish lores and feet (legs black in adults). Immature Little Blue Heron has greenish legs and pale grayish or pinkish lores.
Koczur, L. M., M. C. Green, B. M. Ballard, P. E. Lowther, and R. T. Paul (2020). Reddish Egret (Egretta rufescens), version 1.0. In Birds of the World (P. G. Rodewald, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA.