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Neotropic Cormorant
Phalacrocorax olivaceus

DESCRIPTION:
Neotropic Cormorant
Biguá
Phalacrocorax olivaceus
Length: 700mm. Sexes alike. Bill brownish horn; iris green; bare facial skin and gular pouch, dark yellowish; head, neck, back and rump glossy black; black tail; upper back feathers and scapulars lanceolate, dark greyish brown with green sheen and black feather edges, imparting scaly appearance; wing coverts likewise; scapulars, primaries and secondaries black slightly brownish; underwing coverts and axillaries brownish black; breast, underparts and under tail coverts black. Legs black.
Adults in nuptial plumage show a white band behind the gular pouch that extends from the gape to the lower part of the eye area; on both sides of head, neck and thighs, white filoplumes are present. Juvenals are dark brown overall, somewhat paler on neck and breast; gular pouch is yellow, slightly orange. Chicks are born naked, with a blackish grey skin, and later acquire a blackish down. Habitat and behaviour: inhabits all types of aquatic environments; very common and easily recognised; it is adapted both to marine coasts and freshwater bodies such as rivers, lakes and ponds; occasionally at high altitudes above sea level. It is frequently seen single, in pairs or in groups ranging from 5 to 10 or 20 individuals, according to the availability of food; in breeding colonies and roosting grounds and wherever food is abundant they gather in groups of hundreds of individuals. Feeds on fish, which is often obtained by cooperative foraging groups that swim together in a coordinated fashion, circling around their prey, then diving in unison to capture the fish. To take flight, it must taxi along a certain distance and once airborne it progresses with a quick straight flight and powerful wing beats; commonly seen flying low over the surface, although occasionally flying high. It generally perches on emerging rocks in lakes and rivers, on logs, posts or directly on ground. Of all the Patagonian species, the Neotropic Cormorant is the only one that can perch on trees and shrubs; while roosting during the day it spends a long time with its wings spread-eagled, drying them. Although silent most times, in the nocturnal roosting grounds it utters a vocalisation that resembles that of a pig. Colonial nesters; nests are built with twigs in trees or shrubs and gullies; females lay up to 4 light blue-white eggs covered with a thin calcareous layer.
Range: very common in its dispersal range from Neuquén and Río Negro to Cape Horn, in Chile, and all South America.
Illustrated Handbook of the Birds of Patagonia
Kindless: Kovacs Family
 
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Photographs: Mariano Diez Peña


Birding Patagonia • Birdwatcing in Bariloche, Patagonia, Argentina and Chile.
All Rights reserved. Reproduction of photographs is forbidden without permission from the authors.
Photographs on the website: Mariano Diez Peña