Statistical Models for Population Reconstruction Using Age-at-Harvest Data

Statistical analyses based on maximum likelihood methods are presented to jointly estimate harvest rates, survival, recruitment, and population abundance from age-at-harvest data. To perform the population reconstruction from the age-at-harvest data, auxiliary field data and information on harvest reporting rates are required. The statistical methods permit tests of model assumptions, goodness-of-fit, and standard errors and confidence intervals for all estimated demographic parameters. We illustrate the methods using harvest data and radiotelemetry studies of elk (Cervus elaphus) from northern Idaho, USA, 1988-1993. We compare results with abundance estimates using an aerial sightability survey on the same herd. The maximum likelihood methods for age-at-harvest analysis provide a comprehensive framework for population reconstruction with abundance estimates comparable to field survey techniques.