As molecular techniques become more advanced, scientists and practitioners are calling for restoration to leverage genetic and genomic approaches. We address the role of genetics in the restoration and conservation of cutthroat trout in the western U.S., where new genetic insights have upended previous assumptions about trout diversity and distribution. Drawing on a series of examples, we examine how genetically pure trout populations are identified, protected, and produced through restoration practices. In landscapes that have been profoundly impacted by human activities, genetics can offer seemingly objective metrics for restoration projects. Our case studies, however, indicate that (1) genetic purity is fragile and contingent, with notions of what genetics are “pure” for a given species or subspecies continually changing, and (2) restoration focused on achieving “genetically pure” native populations can deliberately or inadvertently obscure the socio-ecological histories of particular sites and species, even as (3) many “genetically pure” trout populations have endured on the landscape as a result of human modifications such as roads and dams. In addition to raising conceptual questions, designations of genetic purity influence policy. These include tensions between restoring connectivity and restoring genetic purity, influencing Wild and Scenic River Act designations, and the securing of water rights.more »
Wild, Native, or Pure: Trout as Genetic Bodies
Advances in genetics and genomics have raised new questions in trout restoration and management, specifically about species identity and purity, which fish to value, and where these fish belong. This paper examines how this molecular turn in fisheries management is influencing wild and native trout policy in Colorado. Examples from two small Colorado watersheds, Bear Creek and Sand Creek, illustrate how framing trout as genetic bodies can guide managers to care for or kill trout populations in the interest of rectifying decades of genetic disruption caused by human activity. While trout management has typically relied on human intervention, the turn to genetic science is prompting new classifications of lineage and taxa, altering long-standing conservation priorities, and reorienting the manipulation of biological processes such as reproduction and dispersal. As a result, other social and ecological factors may be pushed to the margins of management decisions. These changes warrant greater conversation about the consequences of molecular analyses and the values embedded in trout science and conservation more broadly.
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