FORAGING FLIGHTS OF BREEDING THICK-BILLED MURRES (URIA-LOMVIA) AS REVEALED BY BIRD-BORNE DIRECTION RECORDERS

A bird-borne data logger, which stores Right directions at regular int ervals, was used to reveal the foraging patterns of Thick-billed Murre s (Uria lomvia) breeding at Latrabjarg in northwestern Iceland. Tracke d birds traveled 10 to 168 km one-way to foraging sites in a narrow se ctor to the northwest of the breeding colony. The pattern of foraging activity was rather constant. Outbound birds stopped briefly several t imes, possibly testing prey availability. The longest stops occurred a t sites close by the turning point of the outbound journey. During the inbound flight, stops were less frequent and shorter than on the outb ound flight, suggesting that the sequence of stops was not the express ion of a disturbance caused by the instruments.