Muskrats as a bellwether of a drying delta

A dramatic decline in muskrat populations in Canada’s Peace-Athabasca Deltareveals the severe impact of wetland loss on even generalist species, despite protection. Using population surveys, habitat mapping, and genetic data from 288 individuals, researchers found that while floods can temporarily boost populations to ~500,000, drying reduces them drastically (~10,000). Agent-based modeling showed the population functions as a metapopulation, with dispersal along riparian corridors enabling rapid recovery. Genetic analysis indicated long-term population bottlenecks (Ne: 60–127), suggesting historical declines. The study highlights how wetland loss in protected areas disrupts source-sink dynamics, threatening biodiversity even for adaptable species like muskrats.

Ward, E. M., Solari, K. A., Varudkar, A., Gorelick, S. M., & Hadly, E. A. (2021). Muskrats as a bellwether of a drying delta. Communications Biology, 4(1). https://doi.org/10.1038/s42003-021-02288-7