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HERONS (ARDEIDAE; 18+ SPECIES) Worldwide family of typically long-necked,

long-legged birds with dagger-like bills; usually near water. Fly with neck retracted in bulge,

unlike ibises, spoonbills, storks. Ages differ or similar, attain adult appearance in 1–3 years.

Bare parts often brighten or change color strikingly for brief periods at height of breeding

season. Most species nest colonially in trees and marshes, often in mixed-species aggregations.

Usually quiet except when disturbed or interacting at colonies; bitterns and tiger herons,

however, have ‘songs.’

WESTERN CATTLE EGRET  Bubulcus ibis 45–53cm. Fairly small, compact

white heron usually found near cattle, horses, tractors, that flush up prey from

fields and pastures; also flooded fields, lakeshores, but not habitually wading in

wetlands like most herons and egrets. Nests in reedbeds, trees, often with other

wading birds, cormorants. Social, usually in groups, locally 100s. Distinctive,

with stocky shape, yellowish bill, dark legs; cinnamon-buff plumes on crown,

chest, and back most extensive on breeding adult, can be absent on 1st-year. In

flight note rather stocky shape without strong deep neck bulge of Snowy Egret.

At height of breeding, bill and lores flush salmon, legs scarlet. Fledgling bill can

be blackish, soon like adult. SOUNDS: Gruff clucks and grunts, mainly when nesting. STATUS: Fairly

common to locally common in lowlands, in smaller numbers to 2000m. (Americas, Africa, and W Eurasia.)

SNOWY EGRET  Egretta thula 49–59cm. Elegant, fairly small white egret of

varied wetland habitats from beaches and river mouths to small ponds,

lakeshores, mangroves. Singles or loose groups; hunts while wading or waiting,

often dashing rather actively in shallows. Note slender black bill and contrasting

yellow lores; adult has shaggy crest, ornate back plumes, yellow feet contrasting

with blackish legs; lores flush orange at height of breeding. Fledgling bill can be

yellowish, tipped black, soon like adult; 1st-year has greenish-yellow feet, hind

edge to legs, cf. 1st-year Little Blue Heron. SOUNDS: Varied guttural rasps and

croaks, averaging throatier than Little Blue Heron; higher, more nasal than

American Great Egret. STATUS: Fairly common to locally common Sep–Apr, mainly below 1500m; smaller

numbers in summer (mainly nonbr. imms.); breeds locally in nw. lowlands, perhaps elsewhere. (Americas.)

*AMERICAN GREAT EGRET  Ardea [alba] egretta 84–99cm. The only large

white heron in Costa Rica, found in a wide variety of wetland habitats from

roadside ditches and flooded fields to coastal lagoons, estuaries, mangroves.

Mostly singles or small groups, but 100s can gather at favored feeding sites with

aggregations of other wading birds. Note wholly white plumage, yellow bill,

blackish legs and feet; adult has long ornate back plumes. At height of breeding,

lores flush bright green and maxilla is extensively black. Cf. much smaller Cattle

Egret. SOUNDS: Varied, deep guttural calls, often with creaky quality; average

less stentorian than Great Blue Heron, lower and harsher than Snowy Egret.

STATUS: Fairly common to locally common Sep–Apr, mainly below 1500m; smaller numbers in summer

(mainly nonbr. imms.); breeds locally in nw. lowlands, perhaps elsewhere. (Americas.)

White Herons in Flight (opposite, far right) are best identified by a combination of structure and

coloration of bare parts; smaller species have quicker wingbeats, more often in flocks.

Western Cattle Egret is stockiest, lacking pronounced deep neck bulge of other species, always with

yellow bill.

Juv. Little Blue Heron very similar to Snowy Egret but with pale, black-tipped bill, uniformly pale

greenish legs and feet; wing-tips have fine dark tips visible with good view.

Snowy Egret has distinct neck bulge, black bill, contrasting yellow feet.

White morph Reddish Egret larger and rangier than Snowy and Little Blue, with very long blackish

legs, slender bill.

American Great Egret is largest with relatively slow wingbeats, big yellow bill, black legs.