Migratory patterns of Ospreys (Pandion haliaetus) from central Norway

Abstrakti

Migratory behaviour is subject to intraspecific variation and may be determined by the age, sex and population origin of individuals. Here we equipped eight juvenile Ospreys (Pandion haliaetus) with GPS-based satellite-transmitters to investigate their migratory behaviour from a recently re-established breeding area in central Norway. Migration routes fanned out widely across Europe, and migratory behaviour differed between individuals. Five of the eight Ospreys completed their first southward migration to wintering areas in tropical Africa. They travelled a median distance of 7,482 km and spent from 21 to 92 days on their journeys. Median travel distance was 120% longer than a straight-line distance. Stopover sites were located just before or immediately after crossings of geographical barriers and the differences in the time spent on the migratory journeys was mainly a consequence of the number of stopover days.