PARENT SESSION
Oral Session # 57: Evolutionary Ecology II: Animal.
Presiding: S Juliano
Wednesday, August 6. 1:30 PM to 5:00 PM, SITCC Meeting Room 201.

Can harvest refuges counteract the effect of evolutionary change in body size caused by size selective harvesting?

Tenhumberg, Brigitte^{*,1, 2}, Tyre, Andrew^{1, 2}, Pople, Anthony ¹, Possingham, Hugh¹, ¹ University of Queensland, St. Lucia, QLD, Australia² University of Nebraska-Lincoln, Lincoln, NE

ABSTRACT- In wildlife harvesting the selection criteria for targeted animals is often a large body size. There is increasing evidence that such size selective harvesting can lead to a directional change in body size in heavily harvested ecosystems. We constructed a stochastic simulation model to explore the possible evolutionary responses to size selective harvesting, and the effects of different management strategies. In particular we examined the effects of harvest refuges and minimum size regulations in kangaroo populations in eastern Australia. Our modeling results suggest that when an entire population is subject to size-selective harvesting this is likely to result in smaller kangaroos of a given age. The effect of size-selective harvesting increases with increasing harvesting rate and increased minimum size of the harvested animals. In scenarios with moderate dispersal from an un-harvested population all effects of harvesting on genetic structure are negligible.

Key words: wildlife harvesting, individual based model, dispersal