Developing seasonal multi-layer network models to evaluate cumulative impacts on Arctic ecosystems

The Arctic is facing the highest rate of global warming on Earth and rapid industrial development. Major environmental transformations such as permafrost thawing or sea ice reduction are affecting wildlife. However, how ecosystems and the species that compose them will respond to multiple stressors (e.g. climate change, industrial shipping and resource extraction) is still poorly understood. In the Arctic, strong seasonality promotes multiple exchanges (e.g. energy, contaminants) among ecosystems (terrestrial and marine), including distant ones, due to wind, oceanic currents, and animal migrations. Understanding the complexity of arctic food webs in changing environments requires modeling interconnections between ecosystems and species interactions. At the same time, it is important to document changes occurring in northern environments and especially in animal abundance and distribution, using advanced technologies and by promoting community-based biodiversity monitoring. It is crucial to include such information in predictive models to evaluate how Arctic biodiversity is likely to be affected by environmental changes and anthropogenic activities and how these changes will impact ecosystem services and ultimately northern communities. Such models will be helpful to guide future decisions to mitigate the effects of multiple stressors. More specifically, our project will 1) Develop new models of the tundra food-webs that incorporate seasonality, animal migration and interactions with marine and southern ecosystems; 2) Prioritize monitoring activities on key species and processes occurring during the winter period to fill important knowledge gaps in developing seasonal models; 3) Promote and support community-based and citizen science programs with northern communities to address environmental issues that matter to Northerners and scale-up spatially and temporally (i.e. year-round) biodiversity monitoring; and 4) Maintain long-term ecosystem-based monitoring programs to feed and test ecosystem models. In our models, existing data will be combined to new field studies conducted on Bylot Island, around the community of Pond Inlet, and at Alert (Canadian Forces Station) on the abundance and movements of predators and migratory birds, and the interactions between wildlife, snow conditions, contaminants and diseases. Observations made by Northerners will complement data collected by scientists because Northern inhabitants are sentinels that can track changes in their environment, especially during winter. Our project will also contribute to capacity building in the North by training Northerners and graduate students.