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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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This content will become publicly available on May 13, 2026
Defining hybridization thresholds for native species conservation in the genomic era
ABSTRACT Human-induced hybridization among genetically distinct groups of fish is a widespread and complex problem in fisheries management. A particularly challenging facet of human-induced hybridization is deciding which fish should be prioritized for conservation action or investment, and which should not. The increasing availability of genomic data in fisheries management demands that explicit hybridization frameworks and associated hybridization thresholds be developed, as increasing resolution will inevitably demonstrate that small amounts of nonnative ancestry are present in populations or species that were previously thought to be nonhybridized. A key question then becomes, how do we make rational decisions regarding resource prioritization for populations or species with, for example, 10, 1, 0.1 or even 0.01% nonnative ancestry? We use extensive data from Westslope Cutthroat Trout Onchorhynchus lewisi to describe how objective, data-based decision frameworks can be developed to help managers conserve genetic variation, while minimizing nonnative ancestry and the risk of outbreeding depression. While the conservation implications of hybridization are nuanced and context-dependent, the approach described herein is general and can be extended to other species.
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- Award ID(s):
- 1652278
- PAR ID:
- 10613583
- Publisher / Repository:
- Fisheries
- Date Published:
- Journal Name:
- Fisheries
- ISSN:
- 0363-2415
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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