Capture-Recapture Models Allowing for Age-Dependent Survival and Capture Rates

A K-sample capture-recapture model for an open population of animals, which allows for different identifiable age categories to have different survival and capture probabilities, is developed. Explicit maximum likelihood estimators of population size and survival rates, together with their asymptotic variances and covariances, are given. A test of whether survival and capture rates are independent of age is shown to be of simple hypergeometric form. An illustrative example based on resighting data of neck-collared giant Canada geese (Branta canadergsis maxima) is presented. The relationship of this model to other capture-recapture and band-recovery models is discussed.