Amphibian population dynamics in disturbed landscapes

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Amphibian populations worldwide are facing population declines and extinctions, more so than either birds or mammals. With their complex life cycles (aquatic and terrestrial life stages), pond-breeding amphibians pose an interesting challenge. Pond-breeding amphibians use different habitat types during different life stages and at different times of the year. Movements between habitat types in a given landscape are limited relative to other vertebrates (< 1 km), which makes amphibians ideal candidates to investigate the effects of habitat disturbances on movements and demographic parameters. Yet, several parameters (e.g., survival, recruitment) necessary to quantify population dynamics in relation to human disturbances remain to be estimated. This is especially true in boreal regions, at the northern range limit of many species, with logging activities moving North and roads being built to access mining or forest resources. The current proposal focuses on modeling Amphibian Population Dynamics in Human-disturbed Landscapes, and combines fundamental and applied components. In this research program, I will quantify the effects of roads and forest practices on the demographic parameters of several pond-breeding amphibian species, through replicated and manipulative field experiments and capture-mark recapture studies. Over the next five years, my research objectives will consist in: 1) quantifying the effect of roads and car traffic on amphibian pond colonization; 2) quantifying the effect of roads on breeding probability, survival, and fitness of individuals, and their repercussions on population persistence; 3) quantifying the effect of habitat complexity (coarse woody debris and canopy openness) on the colonization of artificial ponds by amphibians; and 4) estimating carry-over effects of environmental conditions experienced during early life stages on the survival at later life stages. Beyond life history strategies and carry-over effects, the novel and significant aspects of my work include the role of roads and woody debris on amphibian population processes in boreal regions.