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dc.contributor.advisorHammond, Philip S.
dc.contributor.advisorSantos, Ricardo Serrão
dc.contributor.authorSilva, Monica Almeida
dc.description.abstractThe ranging behaviour, habitat preferences, genetic structure, and demographic parameters of bottlenose dolphins living in the Azores were studied using data collected from 1999 to 2004. Only 44 dolphins out of 966 identified were frequently sighted within and between years and showed strong site fidelity. The remaining individuals were either temporary migrants from within or outside the archipelago, or transients. Estimates of home range size were three times larger than previously reported for this species, possibly as a result of the lower availability of food resources. Mitochondrial DNA sequences showed very high gene and nucleotide diversity. There was no evidence of population structuring within the Azores. The Azorean population was not differentiated from the pelagic population of the Northwest Atlantic, suggesting the "unproductive" waters of the Atlantic do not constitute a barrier to dispersal. Population size, survival and temporary emigration rates were estimated using open-population models and Pollock's robust design. A few hundreds of dolphins occur in the area on a given year, though the majority should use it temporarily, as suggested by the high emigration rates. Bottlenose dolphins preferentially used shallow areas with high bottom relief. Temporal and spatial persistence of dolphin-habitat associations documented in this study further supports the idea of a close relationship between certain bathymetric features and important hydrographic processes and suggests the occurrence of prey aggregations over these areas may be, to some extent, predictable. Several results of this study suggest there are no reasons for concern about the status of this population. Yet, the resident group may be negatively affected by increasing pressure from the whale watching activity. Although the proposed Marine Park constitutes important habitat for resident dolphins, at present, the area is clearly insufficient to satisfy their spatial requirements and its conservation value may be limited.en
dc.format.extent2522007 bytes
dc.publisherUniversity of St Andrews
dc.rightsCreative Commons Attribution-NonCommercial-NoDerivs 2.5 Generic
dc.subjectBottlenose dolphinsen
dc.subjectRanging behaviouren
dc.subjectCapture-recapture methodsen
dc.subjectDemographic parametersen
dc.subjectHabitat modellingen
dc.subjectPopulation structureen
dc.subjectGenetic structureen
dc.subject.lcshBottlenose dolphin--Azoresen
dc.subject.lcshBottlenose dolphin--Genetics--Azoresen
dc.subject.lcshBottlenose dolphin--Conservation--Azoresen
dc.subject.lcshCetacea populations--Azoresen
dc.subject.lcshPopulation biologyen
dc.titlePopulation biology of bottlenose dolphins in the Azores archipelagoen
dc.contributor.sponsorFundação para a Ciência e Tecnologia (Portugal)en
dc.type.qualificationnamePhD Doctor of Philosophyen
dc.publisher.institutionThe University of St Andrewsen
dc.publisher.departmentSea Mammal Research Unit, School of Biologyen

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Creative Commons Attribution-NonCommercial-NoDerivs 2.5 Generic
Except where otherwise noted within the work, this item's license for re-use is described as Creative Commons Attribution-NonCommercial-NoDerivs 2.5 Generic