Grants and Contributions:

Grant or Award spanning more than one fiscal year (2017-2018 to 2020-2021).

The Great Lakes basin supports a $7 billion fishery that is increasingly threatened by climate change andx000D
aquatic invasive species. Accurate risk assessments are urgently needed to help identify and prioritize invasivex000D
species that pose the greatest ecological threats to the basin. Indeed, the new aquatic invasive speciesx000D
provisions in the federal Fisheries Act and the 2012 Great Lakes Water Quality Agreement commits Canada tox000D
manage these threats based on scientific assessments of the ecosystem impacts of both established andx000D
high-risk invaders, and the potential influence of climate change on invaders. Risks posed by current andx000D
future invaders are being transformed by higher water temperatures that can alter the growth performance,x000D
feeding efficiency and competitive interactions of invaders and native species, with potentially negativex000D
consequences for food webs that can result in unhealthy ecosystems. However, previous risk assessments in the Great Lakes have not considered how invasion threats are influenced by climate change. To address this gap, we will use an innovative experimental approach that tests the impact of invasive fishes relative to the baseline impacts of native fishes on the broader ecological community. We will conduct these tests in water temperatures projected under different warming scenarios for the Great Lakes. Species tested will include Eurasian Tench, which is an immediate invasion threat to the Great Lakes, and goldfishes (Goldfish, Prussian Carp, Crucian Carp), which are an overlooked group of highly invasive fishes that are increasing in abundance in North America. Climate-warming scenarios will also be incorporated into demographic and hydrodynamic models to assess the ability of Asian (Bighead, Black, Grass and Silver) carps to spawn, survive and overwinter in Great Lakes tributaries. In addition, we will revise risk assessments previously conducted for several hundred freshwater fish species sold as food or pets. This project will combine scientific and management expertise through a collaborative partnership with Fisheries and Oceans Canada.