Living on the edge: Traits of freshwater fish species at risk in Canada

Abstract

Abstract The native ranges of many species in North America reach their northern extent in southern Canada, which results in several aquatic species with core populations found farther south being assessed as at risk by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and receiving protection under the Species at Risk Act (SARA). To determine traits that predict at‐risk status for freshwater fishes in Canada a classification and regression tree analysis was performed using a suite of ecological and life‐history traits, and the species’ distributions in Canada. Range‐edge distribution in Canada was a significant predictor of a species assessed as at risk by COSEWIC and to be listed as at risk under SARA. Other predictive traits included Balon reproductive guild, reproductive age/maximum age ratio, and lifespan. Species with economic value were also not likely to be assessed as at risk by COSEWIC. Analyses showed greater inconsistency in listing status under SARA than COSEWIC assessment, and a bias toward not listing species, despite predicted at‐risk status, was evident. The predictive models may prove useful in making future conservation decisions and highlight species that should have their status (re)assessed.