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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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The Invasion Ecology of Sleeper Populations: Prevalence, Persistence, and Abrupt Shifts
ABSTRACT It is well established that nonnative species are a key driver of global environmental change, but much less is known about the underlying drivers of nonnative species outbreaks themselves. In the present article, we explore the concept and implications of nonnative sleeper populations in invasion dynamics. Such populations persist at low abundance for years or even decades—a period during which they often go undetected and have negligible impact—until they are triggered by an environmental factor to become highly abundant and disruptive. Population irruptions are commonly misinterpreted as a recent arrival of the nonnative species, but sleeper populations belie a more complex history of inconspicuous occurrence followed by an abrupt shift in abundance and ecological impact. In the present article, we identify mechanisms that can trigger their irruption, and the implications for invasive species risk assessment and management.
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- Award ID(s):
- 2025982
- PAR ID:
- 10316453
- Date Published:
- Journal Name:
- BioScience
- Volume:
- 71
- Issue:
- 4
- ISSN:
- 0006-3568
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/biosci/biaa168
