BODY MASS INCREASE, MIGRATION PATTERN AND BREEDING GROUNDS OF DUNLINS, Calidris a. alpina, STAGING IN THE DUTCH WADDEN SEA IN SPRING

Abstract

Though a lot is known about the Dunlin, a highly variable wader species in many respects, there is still uncertainty whether substantial numbers of this species migrating through W. Europe in spring, breed as far as Siberia. Data on numbers, turnover, recoveries, body mass and bill length of the Dunlin, collected in spring in the eastern part of the Dutch Wadden Sea, are presented. Two kind offattening strategies are clearly distinguished and seem to be used by two different groups of the subspecies a/pina. The groups are temporally segregated: one is present in April the other in May. It is argued that the latter one breeds in Siberia as far as the western part of the Taymyr peninsula.