Are There Specific Adaptations for Long- Distance Migration in Birds? The Search for Adaptive Syndromes: Outline of the European Science Foundation Workshop

摘要

Twice a year, numerous species of almost all bird genera face the challenge of overcoming distances of up to several thousand kilometers between breeding and wintering grounds. Migrations enable birds to explore highly seasonal habitats and exploit resources during their peak abundance, primarily for reproduction. Time spent in migration can exceed that spent in other phases of the annual cycle. Metabolism is at its peak, due to high catabolism required during the energetically costly flight, while anabolism predominates during subsequent stopover periods. With respect to time and energy spent, and resources that are accumulated and depleted, migration is a dominating phase within the annual cycle of long-distance migratory birds. In the frame of the "Optimality in Bird Migration" program of the European Science Foundation, scientists were able to investigate, discuss, and exchange their thinking about the phenomenon of bird migration. The main issues of the "optimality approach" is that each individual is selected to maximize its individual fitness, and for the migration program it has been proposed to do so by either (1) minimizing time, (2) minimizing energy costs of transport, or (3) predator minimization.