Abstract
Habitat loss and overexploitation extirpated American black bears (Ursus americanus) from most of the Central Appalachians, USA, by the early 20th Century. To attempt to restore bears to the southwestern portion of this region, 2 reintroductions that used small founder groups (n = 27 and 55 bears), but different release methods (hard vs. soft), were conducted during the 1990s. We collected hair samples from black bears during 2004-2016 in the reintroduced Big South Fork (BSF) and Kentucky-Virginia populations (KVP), their respective Great Smoky Mountains (GSM) and Shenandoah National Park (SNP) source populations, and a neighboring population in southern West Virginia (SWV) to investigate the early genetic outcomes of bear reintroduction. Despite having undergone genetic bottlenecks, genetic diversity remained similar between reintroduced populations and their sources approximately 15 years after the founder events (ranges: AR = 4.86-5.61; HO = 0.67-0.75; HE = 0.65-0.71). Effective population sizes of the reintroduced KVP and BSF (NE = 31 and 36, respectively) were substantially smaller than their respective SNP and GSM sources (NE = 119 and 156, respectively), supporting founder effects. Genetic structure analysis indicated that the hard-released (i.e., no acclimation period) KVP founder group likely declined considerably, whereas the soft-released BSF founder group remained mostly intact, suggesting superior effectiveness of soft releases. Asymmetrical gene flow via immigration from the SWV has resulted in the KVP recovering from the initial founder group reduction. Sustained isolation, small NE, and small population size of the BSF may warrant continued genetic monitoring to determine if gene flow from neighboring populations is established or NE declines. For future bear reintroductions, we suggest managers consider sourcing founders from populations with high genetic diversity and soft-releasing bears to locales that are, if possible, within the dispersal capability of extant populations to mitigate the potential consequences of founder effects and isolation.
Original language | English |
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Pages (from-to) | 119-133 |
Number of pages | 15 |
Journal | Ursus |
Volume | 29 |
Issue number | 2 |
DOIs | |
State | Published - May 1 2019 |
Bibliographical note
Funding Information:This study was primarily funded by U.S. Federal Aid in Wildlife Restoration administered by Kentucky Department of Fish and Wildlife Resources. Supplemental funds were provided by University of Kentucky, University of Tennessee, U.S. Forest Service, U.S. Geological Survey, U.S. National Park Service, Virginia Department of Game and Inland Fisheries, and West Virginia Division of Natural Resources. We thank L. Harris, D. Paetkau, and other personnel at Wildlife Genetics International for expedient genotyping. We are grateful for the helpful comments and suggestions provided by J. E. Swenson, F. T. van Ma-nen, R. K. Rowe, the Associate Editor, and anonymous reviewers. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Author J. T. Hast was an employee of the primary funding entity; to the best of our knowledge, no other potential conflict of interest— financial, relational, or other—exists.
Publisher Copyright:
© 2019 E-flow BioOne. All rights reserved.
Keywords
- Appalachia
- Kentucky
- Tennessee
- Ursus americanus
- Virginia
- West Virginia
- bear
- bottleneck
- effective population size
- genetic diversity
- genetic structure
- reintroduction
ASJC Scopus subject areas
- Animal Science and Zoology
- Nature and Landscape Conservation
- Management, Monitoring, Policy and Law