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Lesser Upland Goose
Chloephaga picta

DESCRIPTION:
Lesser Upland Goose
Cauquén Común
Chloëphaga picta
Length: 750mm. Sexes unlike. Male: bill black; iris dark brown; head, neck, breast, belly, thighs and undertail coverts, pure white; flanks and upper back, white with transversal black barring. Scapulars and tertiaries brownish grey; lower back, rump and uppertail coverts pure white; tail black with greenish sheen except for one or two outer rectrices on either side, which are white; lesser and median wing coverts pure white; greater wing coverts dark grey on inner vexilla and metallic green on outer vexilla with purplish sheen, forming the speculum on secondaries, which are white, same as underwing coverts and axillaries; primaries are very dark brownish grey. Legs black.
Female: bill and iris same as male; head and neck rusty cinnamon; breast and upper back rusty cinnamon with transversal black barring; flanks and belly white with wide black barring, scapulars and tertiaries brownish grey, browner than male; lower back, rump, uppertail coverts and rectrices black with greenish sheen. Wings similar to male. Legs yellow.
Juveniles and immature are quite similar to adults but overall coloration is paler and barring is less contrasting; on white parts male is slightly tinted brownish, and speculum is dull brownish in both sexes.
These descriptions are for the monotypic race, Chloëphaga picta picta. There are two races or subspecies: one whose male is entirely striped or barred, Chloëphaga picta dispar, and another one, restricted to Islas Malvinas, Chloëhaga picta leucoptera. The male in Chloëphaga picta dispar shows breast, belly and flanks entirely striped with black, on the head and neck coloration is greyish on account of the fine and plentiful blackish barring; back is dark grey; lower back, rump, uppertail coverts and tail are entirely black with a greenish sheen. The female of this race shows head and neck rusty brown. The race Chloëphaga picta leucoptera, restricted to Islas Malvinas, is similar to the monotypical or nominate race but slightly larger and the female has finer black barring, which accounts for its rusty cinnamon overall appearance. The form whose male is white (Chloëphaga picta picta) occupies the pre-Andean Patagonian region and adjacent areas, extending to the central regions towards the east, whereas the race whose male shows a striped breast (Chloëphaga picta dispar) occurs mostly in Tierra del Fuego and east of Patagonia, occasionally in the pre-Andean region. As there is overlapping among individuals of both races, intermediate specimens can be found with features common to both subspecies. Habitat and behaviour: very common throughout most of the dispersal area, it inhabits open fields, sometimes far from water bodies, although it prefers freshwater areas; during the day it forages, picking with its bill herbs and tender grasses which make up its staple food; at nightfall it flies to the ponds or river banks to spend the night near the water in large flocks. Essentially gregarious, although during the breeding season the flocks disperse in pairs that nest along the shores of streams, rivers and ponds, a few hundred metres away from each other.
The nest is built in hollows on the ground, concealed among grasses and bushes; the bottom is lined with grass, then covered with abundant down and feathers; up to eight creamy white eggs are laid; the female is in charge of incubation, the male remains near the nest, mounting guard with determination and fierceness. When chicks hatch both parents share rearing duties.
In the event of danger chicks get in the water followed by their parents, swimming and diving effortlessly; adults are also good divers; to become airborne, both from the water and from land, they must taxi along short distances; once they take off flight is quick and purposeful.
During autumn they undertake long migrations from their southern areas, from Tierra del Fuego, Isla de los Estados and Santa Cruz as far north as Buenos Aires and La Pampa; the return to their breeding and residence grounds takes place from mid August until end of September.
Populations of the pre-Andean region also move to the north, where there is overlapping with the race whose male is striped, also reaching Mendoza on the west. Extremely common until not long ago, at present populations are decreasing considerably due to anthropogenic environmental pressures.
Range: the distribution of the Lesser Upland Goose includes Patagonia from Neuquén and Río Negro to Tierra del Fuego, Isla de los Estados and Islas Malvinas.
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