Conservation of herpetofauna in northern landscapes: Threats and challenges from a Canadian perspective

The scientific community is increasingly aware that many amphibian and reptile species have experienced dramatic decreases in abundance and distribution, with at least 43% of amphibian species exhibiting population declines and 19% of all reptile species threatened with extinction since 2000. Species suffer from a suite of threats including habitat destruction, alteration and fragmentation, introduced species, over-exploitation, climate change, UV-B radiation, chemical contaminants, diseases and the synergisms among them. These worldwide threats are also present in northern landscapes and in Canada in particular where 20 amphibian and 37 reptile species are listed as at-risk by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). In fact, with more than 80° in longitude and 40° in latitude, Canada presents both a diversity of northern ecosystems and a range of threats to its herpetofauna at least equal to other countries. The physical scale of Canada, its varied climate, its economic realities, and the legislative differences among levels of government and their respective mandates have long challenged traditional approaches to conservation. However, science and stewardship are leading forces in the conservation of emblematic species at risk in Canada and can serve to inform best practices elsewhere. Recent advances in data analysis and management have transformed our understanding of populations in northern landscapes. Canadian amphibians and reptiles, most of which are cold-adapted species at the northern edge of their distribution, can serve as case studies to improve modeling of population dynamics, create cogent, science-based policies, and prevent further declines of these taxa.