Migratory movements and mortality of Danish avocets Recurvirostra avosetta

Abstract

Recoveries of 440 Avocets ringed in Denmark were analysed to describe the migration pattern of the Danish population throughout the year. The overall recovery rate is 3.4%, with the recovery rate for birds ringed as adults being larger than the recovery rate for birds ringed as chicks (23.9% vs. 3.1%). The mortality of the Danish population reached 57.8% during the first year of life and 32% for older birds. Danish Avocets are truly migratory; the first birds leave Denmark in August and most birds have left the country by October. Most recoveries are from France (60%), Spain (12%) and Portugal (16%), especially at coastal wetlands along the Atlantic seaboard. No difference was found between young and old birds with respect to winter quarters. The return migration to the Danish breeding grounds occurs in March. Adult birds showed a higher rate of return to their ringing area (70%) than birds ringed as chicks (38%). © 1995 Taylor & Francis Group, LLC.