La Tour du Valat

Institut de recherche pour la conservation des zones humides méditerranéennes

Titre :	Juvenile plumage of Barnacle Geese Branta leucopsis in the course of the first winter.
Auteurs :	Birgit ten Thoren, Auteur ; Barbara Ganter, Auteur
Type de document :	Article
Dans :	Vogelwelt (Die) (123(6) 2002)
Article en page(s) :	307-310
Résumé :	One way to obtain information on breeding success of Palearctic breeding geese wintering in Europe is to count the number of juvenile and adult individuals. While juvenile Brent Geese can be easily distinguished from the adults, this is much more difficult in Barnacle Geese. However, their first-year plumage lacks the contrasting black-and-white features of the adults, wing-coverts are grey-brown with faint buff margins, feathers are lacking contrasting pale edges and have rounded tips. Photographs of young birds of known age show changing plumage characteristics during the first winter. This means that in spring some young birds already have the more contrasting black-and-white pattern of the adults. Therefore it is recommended to count the proportion of juvenile Barnacle Geese as early in autumn as possible after they have arrived at the wintering grounds.

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