The influence of body size and sex on the characteristics of harbour seal foraging trips
Most pinnipeds disperse from centralised terrestrial sites to forage at sea, but the factors that result in variation in foraging-trip characteristics remain unclear. We investigated the influence of sex and body size on the summer foraging activity of radio-tagged harbour seals (Phoca vitulina) fro...
Main Authors: | , , , |
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Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
1998
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Subjects: | |
Online Access: | https://research-portal.st-andrews.ac.uk/en/researchoutput/the-influence-of-body-size-and-sex-on-the-characteristics-of-harbour-seal-foraging-trips(81865ac9-6a54-4f7f-98b3-69073fd78cf5).html http://www.scopus.com/inward/record.url?scp=0032422808&partnerID=8YFLogxK |
Summary: | Most pinnipeds disperse from centralised terrestrial sites to forage at sea, but the factors that result in variation in foraging-trip characteristics remain unclear. We investigated the influence of sex and body size on the summer foraging activity of radio-tagged harbour seals (Phoca vitulina) from Scotland. Mean foraging-trip duration (range 17-257 h) was strongly correlated with mean foraging range (range 4.3-55.0 km), but both were significantly shorter for females. The proportion of time spent at sea, mean trip duration, and mean foraging range were all positively related to body size. Comparison with data from other study areas suggests that both environmental and endogenous factors shape foraging characteristics in this species. These sex and body size related differences in activity pattern and foraging range have important implications for the methodologies currently used to assess the population size, population energy requirements, and diet composition of coastal pinnipeds. |
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