This study, led by the Ministry of Natural Resources and Forestry’s Natural Heritage Information Centre, the ministry’s Climate Change Program, and the Canada-Ontario Agreement Respecting the Great Lakes Basin, used NatureServe’s Climate Change Vulnerability Index (CCVI) to assess the relative vulnerability of 280 species in Ontario’s Great Lakes basin to climate change. The index incorporates a framework that separates a species’ vulnerability into 2 main components: the species’ exposure to climate change in the Ontario Great Lakes Basin and its sensitivity/adaptive capacity. The species assessed included amphibians, birds, bryophytes (mosses and liverworts), fishes, insects and spiders, lichens, mammals, mollusks, reptiles, and vascular plants.
The results showed 175 of the 280 assessed species to be vulnerable to climate change. Eleven were found to be extremely vulnerable, 49 were highly vulnerable, and 115 were moderately vulnerable. The remaining 105 were found to be less vulnerable. Of the 10 taxonomic groups assessed, those depending most on water (mollusks, fishes, amphibians, lichens) were most vulnerable. Vascular plants and mammals varied widely in assessed vulnerability, while birds, insects and spiders, and reptiles were found to be the least vulnerable. The common risk factor for all groups was historical hydrological niche or species’ past exposure to precipitation variations across its range in the Ontario Great Lakes Basin (and hence potential ability to adapt to future change depending on the magnitude). A species’ temperature tolerance, dispersal ability, barriers to movement, habitat specificity, and hydrological requirements were other important traits contributing to its climate change vulnerability.
The results support the development of adaptive conservation strategies aimed at mitigating identified vulnerabilities. They also highlight the importance of considering climate change in managing species at risk and the need for better, more coordinated, and centralized biodiversity and distribution data for all species of conservation concern, particularly invertebrates, lichens, and bryophytes, for which information is limited.