Moving repatriation efforts forward for imperilled Canadian freshwater fishes

Abstract

Freshwater ecosystems are among the most threatened environments on our planet. Disturbances across the terrestrial landscape accrue within freshwater ecosystems and, combined with global stressors such as climate change and invasive species, create a complex situation for recovering imperilled fishes. Given the drastic global decline of freshwater fishes, similarly extreme efforts are needed for their conservation and recovery — repatriation represents one such opportunity. Species repatriation describes the act of releasing a species in areas where extirpation has occurred. Paradoxically, a long history of fish introductions for recreational purposes exists, yet examples of repatriation for imperilled fishes are relatively rare compared with terrestrial species. Stemming from the restoration and species introduction literature, we identify five ecological themes to consider when evaluating repatriation potential of freshwater fishes and suggest that repatriation represents the “drastic” approach needed to achieve meaningful conservation milestones.