Non-Natives, Near-Natives, and Coldwater Fisheries Conservation

Coldwater fisheries around the world face an array of challenges, ranging from warming temperatures to habitat modification and introduced species. Recent advances in genetic and genomic analyses are also reordering long-standing conceptions of fish taxonomy and range, leading to new questions about which organisms belong in particular watersheds as true or “historic” natives, which might be considered “near-natives,” and which are introgressed hybrids or interlopers brought in through human activity (e.g. Lemoine and Svenning, 2022). While these changes are often seen as threats to salmonid and coldwater fish conservation, they also present opportunities to manage biodiversity in new and potentially adaptive ways. In this paper we critically examine efforts in the US Rocky Mountain West to strike a balance between privileging native species, managing near-natives as ecological cognates that may carry advantages of resilience or reproduction, and introducing non-natives as part of managed novel ecosystems that cater to ecological or cultural interests. We focus in particular on two cases of coldwater fish conservation that highlight these dynamics: 1) the management of native cutthroat trout species (Oncorhynchus clarkii) that recent genetic assays have found to be taxonomically different than previously thought, whether due to trans-basin relocations and/or hybridization; and 2) the intentional introduction of sterile, hybrid tiger muskies (a cross between muskellunge [Esox masquinongy] and northern pike [Esox lucius]) to a high-elevation reservoir to control the proliferation of an earlier introduced species, the white sucker (Catostomus commersonii). Both cases illustrate how shifting scientific knowledge and emergent novel ecosystems create new ecological and social dynamics for conservation efforts to negotiate as we turn toward forward-looking strategies that account for biotic novelty, ecosystem function, and cultural interests.

 

Citation: Lemoine, R. T., & Svenning, J. C. (2022). Nativeness is not binary – a graduated terminology for native and non‐native species in the Anthropocene. Restoration Ecology, 30(8), e13636.