Range and movements of the Alpine ChoughPyrrhocorax graculus in relation to human developments in the Italian Alps in summer

Abstract

Eight radio-tagged Alpine Choughs were tracked around Cervinia (Aosta, Italy) in summer 1989 and 1990. Range size varied from 7.1 to 16.7 km2. All of the birds used both alpine meadows and high mountain cliffs but spent on average only 10 % of their foraging time around human developments. Two of the birds in 1989 made regular journeys between meadows and cliffs, taking on average 15.1 min for the journey, spending 24–29 min on the cliffs, 2.9 min on the return crossing and 36–41 min foraging on meadows with other birds, an average round trip of 73–80 min. The birds marked in 1990 visited the cliffs at irregular intervals but the mean times they spent in the two habitats were similar to those measured in 1989 (cliffs, 28.2 min, meadows, 47.5 min). Throughout the study period, the Choughs were largely dependent on alpine meadows, so that any loss or damage to these would be detrimental. Use of an area of meadow was reduced in 1990 compared to 1989 following extensive ski development there. The birds obtained very little compensatory benefits from human developments, at least in July.