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FRIGATEBIRDS (FREGATIDAE; 1+ SPECIES) Very large but lightweight, mostly
black seabirds with long crooked wings, deeply forked tails that can be held closed in a point.
Ages/sexes differ; adult male has inflatable red throat pouch in display; adult appearance attained
in about 5–6 years.
MAGNIFICENT FRIGATEBIRD Fregata magnificens 90–110cm, WS 200–
240cm. Pacific and Caribbean coastal and inshore waters; often around fishing
harbors, roosting on ship rigging, in mangroves at river mouths; does not alight
on water; ranges inland a short distance to drink fresh water and splash-bathe
at small lakes, rivers. Flight easy and buoyant with slow deep wingbeats,
frequent effortless soaring, often in kettles high overhead; plucks food from sea
surface with long hooked bill and also pirates terns, boobies, other seabirds. No
similar species occur in coastal Costa Rica (Great Frigatebird breeds far offshore
on Cocos I.). Adult male wholly glossy black with distensible red throat balloon
inflated mainly in display; female has black head, white chest; juv./1st-cycle has white head and body with
pointed black patches at breast sides. Complex age/sex plumage progression to adult plumage: 2nd-cycle
has mostly white head and body; 3rd-cycle starts to fill in with black on head and belly; 4th-cycle like
adult with variable whitish mottling in black areas; 5th-cycle ostensibly like adult. SOUNDS: Soft wheezy
warbling and bill rattling, mostly in display. STATUS: Fairly common to common along both coasts; breeds
very locally on islands off Pacific coast; very rare wanderer well inland, mainly in stormy weather. (Tropical
Americas and Galapagos.)
PELICANS (PELECANIDAE; 2 SPECIES) Small worldwide family of very large,
heavy-bodied aquatic birds with long bills and distensible throat pouches. Difficult to
misidentify. Ages differ, sexes similar; attain adult appearance in about 3 years. Some seasonal
change in adult appearance. Adults mostly silent, rarely uttering grunts and hisses; begging
nestlings can be noisy.
BROWN PELICAN Pelecanus occidentalis 112–137cm, WS 190–255cm. Essen
tially unmistakable large dark waterbird of coastal and inshore waters, river
mouths, adjacent lagoons, mangroves; nests on inshore islands. Often rests on
sandbars and beaches with gulls, terns, cormorants, other waterbirds, also
perches on pilings, boats, in mangroves. Singles and lines fly low over the waves,
gliding easily between bouts of measured flapping; at times sails and soars high
overhead. Feeds by plunge-diving, twisting abruptly on entry into the water.
Adult silvery gray above, dark below; nonbr. plumage has white head and neck,
dull eyes; breeding plumage has dark brown hindneck, eye becomes white;
post-breeding adult has white crown spotted dusky. Juv/1st-year dark brown overall with white belly,
broad white median stripe on dark underwing; 2nd-year like messy adult. STATUS: Fairly common to
common along both coasts and over inshore waters, especially Pacific where breeds locally; rare and
irregular inland. (Americas.)
AMERICAN WHITE PELICAN Pelecanus erythrorhynchos 145–165cm, WS 240–290cm. Very rare winter
migrant. Huge, mostly white waterbird that could occur at lakes, wetlands, coastal lagoons. Essentially
unmistakable, but at long range in flight, cf. Wood Stork. Singles or groups feed while swimming and
submerging bill, not by diving. Soars readily, at times in kettles with other waterbirds and vultures. 1st-
year has paler, more pinkish face, bill, and legs than adult, extensive black on inner secondaries and greater
coverts, faint dusky wash to upperwing coverts. 2nd/3rd-year has brighter, more orangey face, bill, legs,
less black on upperwings than 1st-year, often develops dark mottling on upperwing coverts. STATUS: Very
rare and irregular nonbr. migrant to both slopes, mainly nw. lowlands, Dec–Apr. (Breeds N America to
Mexico, winters to Cen America.)