Migratory routes and wintering areas of Swedish Black-headed Gull Larus ridibundus populations

Abstract

A total of 1,508 recoveries of Black-headed Gulls Lorus ridibundus ringed as young in Sweden is analysed. There was hardly any evidence of a non-directional juvenile dispersal. Rather young gulls seemed to leave colonies and start migrating in the predominantly southwesterly direction soon after fledging. The recovery data suggest two main migratory routes for Swedish Black-headed Gulls, one along the Baltic coast and across the Danish Isles, the other across Sweden, mainly in the South Central Lowlands, and later along the coasts of Jutland. There are some indications that more northerly populations spend the winter slightly further to the north than more southerly ones. Although a few recoveries were from as far south as Morocco and some from Central Europe, the main wintering areas of Swedish Black-headed Gulls are Britain, The Netherlands, Belgium and France.