DO HARVEST REFUGES BUFFER KANGAROOS AGAINST EVOLUTIONARY RESPONSES TO SELECTIVE HARVESTING?

Authors

Brigitte Tenhumberg, University of Nebraska - LincolnFollow
Andrew J. Tyre, University of Nebraska at LincolnFollow
Anthony R. Pople, University of Queensland
Hugh P. Possingham, University of Queensland

Document Type

Article

Date of this Version

2004

Comments

Published in Ecology, 85(7), 2004, pp. 2003–2017. Copyright 2004 by the Ecological Society of America. Used by permission.

Abstract

There is a wealth of literature documenting a directional change of body size in heavily harvested populations. Most of this work concentrates on aquatic systems, but terrestrial populations are equally at risk. This paper explores the capacity of harvest refuges to counteract potential effects of size-selective harvesting on the allele frequency of populations. We constructed a stochastic, individual-based model parameterized with data on red kangaroos. Because we do not know which part of individual growth would change in the course of natural selection, we explored the effects of two alternative models of individual growth in which alleles affect either the growth rate or the maximum size. The model results show that size-selective harvesting can result in significantly smaller kangaroos for a given age when the entire population is subject to harvesting. In contrast, in scenarios that include dispersal from harvest refuges, the initial allele frequency remains virtually unchanged.

Includes Appendices A-D.