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Brown-hooded Gull
Larus maculipennis

DESCRIPTION:
Brown-hooded Gull
Gaviota de Capucho Café
Larus maculipennis
Length: 420mm. Sexes alike. Bill carmine red; iris dark brown; incomplete white ocular ring; head entirely coffee brown in the form of a hood; neck and underparts mostly white, occasionally dyed pink on the breast, flanks and abdomen. Back and scapulars pale-blue grey; rump, uppertail coverts and rectrices pure white; wing coverts and secondaries pale-blue grey; bend of wing, alula, outer coverts covering the base of primaries and five outer primaries white; the most distal primary shows white on the outer vexilla and, out of these five, the three proximal ones show a black subterminal band, the remaining proximal primaries and coverts covering the base of these are pale-blue grey with a black subterminal band; underwing coverts grey; axillaries white. Legs, toes and web carmine red.
Adult winter plumage or nonbreeding is similar to nuptial dress but the head is white with the preocular region and auricular spot blackish, the occipital area is greyish, the bill and legs are duller than in the summer.
Juvenile: white head with crown, nape and auriculars brownish grey like the top part of the neck, the rest of the neck and underparts are white. Back and scapulars sepia brown; rump and uppertail coverts white; rectrices white with a blackish subterminal band. Lesser wing coverts brownish with grey margins, median coverts grey and brown to tip, greater wing coverts grey; secondaries blackish brown with a grey terminal band; primaries, alula and greater coverts of primaries white. Inner primaries grey with a blackish subterminal band, the two outer primaries are black with a white band in the middle and white tipped. The bill is brownish and black to tip, legs are brownish salmon.
The Brown-hooded Gull is identified with relative ease from the other species of similar gulls, especially by the colour pattern of primaries and colour of head, bill and legs. Habitat and range: very common, it is found mostly in flocks that in their usual roosting, feeding or breeding grounds may gather in very large groups. It frequents ponds, lakes, marshes, rivers, seashores and also open fields. It follows ploughs and trawlers, chiefly feeding on animal matter such as small fish, crustaceans, molluscs and earthworms, worms and insects, and it rounds up its diet with some vegetation.
The Brown-hooded Gull is very well known and protected by farmers on account of it eating all types of invertebrates, which are uncovered in the furrow. In these circumstances it often associates with the Chimango Caracara (Milvago chimango). It often preys on lepidopteron and other plagues. It nests in ponds and marshes with reeds and brush. Nests consist of a semifloating platform made of cattails and other vegetable matter. Clutch size: up to four olivaceous brown eggs with chestnut and grey mottling throughout, but more abundant on the thick end. Both parents take care of incubation, rearing and feeding of chicks. Nesting colonies are very large and noisy. Nestlings often remain in the nest unless an intruder poses a threat and forces them to go into the water, where they can manage ably only a few hours after hatching. In general, colonies change location each year, moving to more favourable places in terms of the quality and abundance of aquatic vegetation. Range: breeds in Buenos Aires, Entre Ríos, Santa Fe, Córdoba, Mendoza, Patagonia and Islas Malvinas; in autumn it migrates to the north of Argentina as far north as Salta, Santiago del Estero and Corrientes. It also occurs in Uruguay and Brazil. In Chile it is found from Cape Horn to Arica.
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