Maintaining biodiversity in managed forests in the face of multiple ecosystem stressors

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Increasing stress from invasive species and climate change will likely be major contributors to biodiversity decline in managed forests. Recovery and long-term persistence of biodiversity will likely only occur through 1) `habitat rescue' (HR) where forest resilience and returning habitat quality are sufficient to maintain positive growth of resident species or 2) an `evolutionary rescue' (ER) whereby external stressors provoke rapid evolution in life history traits that promote fitness and maintain positive population growth. In this proposal, I provide a comprehensive research program that will detail how HR and ER affect biodiversity in managed forests and how HR/ER can be integrated into land-use strategies meant to adapt/transition forests under global change. I have proposed an ambitious series of field experiments/studies that will validate recovery rate of biodiversity through HR and test key assumptions of ER. These experiments will be conducted within a network of ecosystem management studies in Eastern Canada where I have measured biodiversity response of >100 species of ground beetles over the last two decades. These studies build on long-term studies that I have pioneered and employ rigorous, manipulative field experiments required to identify the relative importance of local recruitment/rapid evolution vs regional dynamics governed by dispersal. A unique aspect of this project is a retrospective study of life-history trade-offs in fecundity and dispersal capacity that will be quantified by dissection of preserved ground beetles collected over 20 years. This experiment will allow us to observe any changes in life-history traits related to HR and ER - as they happened. Together these studies will serve to 1) characterize speed of HR, 2) evaluate changes in life history traits in local populations resultant from HR/ER, 3) identify the relevance of regional process like dispersal for HR/ER, 4) evaluate direct and indirect effects of invasive species, 5) integrate effects of HR/ER/climate change on long-term biodiversity response to predict future `bioscapes' under adaptive silvicultural strategies for global change and other land-use scenarios developed through consultation with diverse stakeholders including first nations and rural communities. This research program will provide land-managers and policy makers with quantitative time-tables for recovery of biodiversity. Demonstration of ER in natural communities in managed forest ecosystems would present an entirely new set of strategies to conserve and possibly use forest management to transition biodiversity to future forest landscapes. This constitutes `adaptive forest management' in the most literal sense. It will also predict future `bioscapes' that can be used to assess adaptive silvicultural strategies for climate change as well and more inclusive management scenarios developed with a wider range of stakeholders such as first nations and rural communities.