Jim Cushing
Arizona University
Environmental change and life history strategies: cannibalism and reproductive synchrony
[When and where]
Significant changes have been observed in life history strategies of marine birds nesting on Protection Island National Wildlife Refuge due to a decrease in food resource availability caused by a rise in mean sea surface in the Strait of Juan de Fuca (which lies between western Canada and the United States). For example, data from our field observations, taken over the last decade from glaucous-winged gull colonies on Protection Island, have documented strong correlations among mean sea surface temperature, adult gull cannibalism of eggs, and reproductive scheduling (egg laying timing) of female gulls. We formulate and analyze a general class of stage- structured, population dynamic matrix models which are designed to investigate the dynamics that can result from a decrease in environmental food resource availability and from a resulting increase in cannibalism and certain within-population interactions that occur in response to it. The focus is on model predicted extinction versus population persistence. Mathematically, the study involves the stability and bifurcations of equilibria and synchronous periodic cycles and the occurrence of multiple attractors and Allee effects. If time permits, an adaptive evolutionary version of the model will also be presented and analyzed.
Invited talk Mini-symposium 11
Updated May 13, 2015, by Minus