The behavioural ecology of the threatened Westland petrel (Procellaria westlandica): From colonial behaviours to their migratory and foraging ecology

Abstract

The petrels (Procellariiformes), although regarded as the most successful of the seabirds with a near global distribution, are facing a crisis with almost half of the species threatened with extinction, yet many lack the basic biological data important for their conservation, due to the difficulty of studying these species which spend most of their lives at sea, only returning to land to breed annually. This thesis focuses on the IUCN-listed Vulnerable Westland Petrel (Procellaria westlandica), one of the largest burrowing seabirds, which breeds only in a relatively small area in the Paparoa National Park in Westland, New Zealand, during the austral winter. The major goals were to test specific hypotheses related to the behavioural, migratory, and foraging ecology of this species with critical relevance for its conservation. The major aims were to identify the annual distribution of the Westland Petrel, its migratory dynamics, how these vary between the sexes and seasons, to characterise sex differences in morphological characteristics, and to study the temporal variation in the social and vocalisation behaviours of a nocturnal colonial seabird.