Some Factors Affecting the Size of British Grey Seal Populations
- 1 August 1978
- journal article
- research article
- Published by JSTOR in Journal of Applied Ecology
- Vol. 15 (2) , 401-411
- https://doi.org/10.2307/2402600
Abstract
Age specific survival and fecundity are evaluated for the rapidly increasing British grey seal [Halichoerus grypus Fabricius] population. The effect of changes in these values on the rate of increase of the population are investigated. The only known density dependent mechanism operates on pup survival and has only a small effect on the rate of increase. There is no evidence of a change in age at 1st pregnancy with increasing population size. Small changes in adult survival have a large effect on the population rate of increase, but no natural mechanisms that directly affect adult survival were identified. Ultimate population size appears to be set by the number of potential breeding sites.This publication has 5 references indexed in Scilit:
- Trends in the Size of British Grey Seal PopulationsJournal of Applied Ecology, 1978
- Growth of a fur seal populationPhilosophical Transactions of the Royal Society of London. B, Biological Sciences, 1977
- The Breeding Biology of the Grey Seal, Halichoerus grypus (Fab.), on the Farne Islands, NorthumberlandJournal of Animal Ecology, 1964
- The Analysis of a Catch CurveBiometrics, 1960
- Some Further Notes on the Use of Matrices in Population MathematicsBiometrika, 1948