Integrating life history and spatial ecology variation into conservation plans for turtles

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Across its range distribution, a species displays considerable differences in age and size at maturity, reproductive output, behaviour, and habitat selection among populations. And even within populations, there can be extensive variation among individuals. This variation, in part, represents phenotypic adaptations to local environmental conditions and resources, and needs to be considered in the design of recovery plans for species at risk. The objective of my research program is to examine variation in the wild at multiple levels of organization in the context of local adaptations and species conservation. My research program focuses on multiple species of turtles. From a conservation perspective, turtles are an extremely important group because, of the approximately 300 species world-wide, about 2/3 are declining in numbers as a result of habitat destruction and harvesting for the pet, traditional medicine, and food trades. Conservation initiatives for Canada's turtles should focus on ways to mitigate mortality from vehicular collisions, high rates of nest failure, loss of wetland habitat, and the impact of additive adult mortality on population viability. Recent important work from my group includes population viability analyses for endangered Spotted Turtles that revealed the importance of adult survival for population persistence. We have also made range-wide comparisons of life history traits in endangered Wood Turtles, range-wide comparisons of sexual size dimorphism in Painted Turtles, and have identified and quantified critical habitat for Spotted Turtles and threatened Blanding's Turtles. Our quantification of hibernation site selection in the wild by several species of turtles has revealed that turtles choose sites that allow them to maintain body temperatures just slightly above freezing, probably to reduce energy expenditures and negative metabolic by-products. My current and future work includes tests of several mitigative measures (e.g., artificial nest sites, ecopassages, fencing, nest cages) to curb additive adult mortality and enhance nest success for several species of at risk turtles, and these studies will produce scientifically-based deliverables directly applicable to species recovery.