Pup production and distribution of breeding antarctic fur seals (arctocephalus gazella) at south georgia
A census of the breeding population of Antarctic fur seals (Arctocephalus gazella) at South Georgia was carried out during the 1990/91 breeding season. Using counts of adult females ashore at the breeding grounds during the pupping period, together with corrections for the likelihood of a female bei...
| Published in: | Antarctic Science |
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| Main Author: | |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
1993
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| Online Access: | https://research-portal.st-andrews.ac.uk/en/publications/88d4aa12-359f-4fa2-b4d2-481eff06edd5 https://doi.org/10.1017/S0954102093000045 http://www.scopus.com/inward/record.url?scp=0027882891&partnerID=8YFLogxK |
| Summary: | A census of the breeding population of Antarctic fur seals (Arctocephalus gazella) at South Georgia was carried out during the 1990/91 breeding season. Using counts of adult females ashore at the breeding grounds during the pupping period, together with corrections for the likelihood of a female being ashore at a census and for pregnancy rate (71% in 1990/91), pup production was estimated as 269 000 (95% confidence intervals 188 000–350 000). The breeding population in 1990/91 was reduced at long-term study sites probably because of limited food availability. Data from these sites were used to estimate the pup production of the population had 1990/91 been a typical year. Based on values from 1983/84 to 1990/91, pup production in 1990/91 would have been 378 000 (se = 19 100) if it had been an average year. The annual increase in pup production from 1976/77 to 1990/91 has declined to 9.8% since the initial period of population expansion in the 1950s and 1960s. Increased population size has led to an expansion of the breeding range at South Georgia. |
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