Non-breeding movements of Black-legged Kittiwakes Rissa tridactyla from a North Sea urban colony

Abstract

Early indications of the extensive North Atlantic non-breeding period range of Black-legged Kittiwakes Rissa tridactyla (hereafter Kittiwakes) have been reported using ship-based observations, but detailed knowledge of the migration of pelagic birds was difficult to obtain until the development of geolocators gave long-term tracking capabilities. Non-breeding period movements of several oceanic species have now been determined in detail. The current study aimed to establish the wintering tracks of Kittiwakes from Lowestoft, an urban colony in the east of England, and also to determine the similarity of annual tracks in individual birds. Commencing in 2012, geolocators were fitted to adult Kittiwakes breeding on Claremont Pier, and up to 2018 data from 15 birds were obtained, including up to four years’ tracks from individual birds. It was found that Kittiwakes from Lowestoft had highly varied tracks, covering virtually the whole range of wintering areas of birds from other North Atlantic colonies. However, individual birds showed a high degree of track repetition from year to year.