The Estimation of Animal Population Size by the Removal Method

SUMMARY This paper deals with the problem of estimating the size of an animal population from the numbers in successive catches made under uniform conditions. Methods given by Seber and Le Cren (1967) and Seber and Whale (1970) depend on asymptotic approximations which fail under conditions commonly arising in practice. These difficulties are examined and an alternative approach, based on direct use of the likelihood function without recourse to asymptotic theory, is described. It is shown that this approach avoids the shortcomings of the earlier methods in small-sample situations.