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Landscape associations and population genetics of a generalist carnivore at a range limit

Bailey A. Kleeberg·Robert Charles Lonsinger·Jennifer R. Adams·Lisette P. Waits·W. Sue Fairbanks
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Abstract

American black bear ( Ursus americanus ) sightings have increased in the Oklahoma Panhandle, an area outside of the species’ historical range, prompting an assessment of bears in the region. We used camera traps and an occupancy modeling framework to identify factors influencing bear detection and space-use patterns. We used noninvasive genetic sampling techniques to evaluate genetic diversity, population structure, and bear abundance in the region. During the summers of 2022–2023, we deployed cameras at 160 sites across western Oklahoma (USA) and detected ≥1 bear at 20 sites. The most-supported model from our single-season single-species analysis indicated that bear detection was positively associated with temperature and precipitation, negatively associated with day of year, and differed between years. The most-supported model indicated that bear space use was negatively associated with elevation (β = −0.013, 85% CI = −0.025, 0.000), and positively associated with slope (β = 0.645, 85% CI = 0.305, 0.984) and coarse woody debris counts (β = 1.539, 85% CI = 0.314, 2.765). We deployed 41 hair snares in Oklahoma resulting in the collection of 153 hair samples and received 69 tissue samples from black bears harvested in northeastern New Mexico. Using 11 microsatellite markers, we identified 21 (12M:9F) bears in western Oklahoma, and 69 (40M:29F) in New Mexico. We found evidence that bears occurring in Oklahoma were an extension of a previously documented population that occurred in northcentral New Mexico. We detected significant population-level heterozygote deficiency ( P = 0.013) compared to expectations under Hardy-Weinberg equilibrium. Using capture with replacement models, we estimated 26 (95% CI = 19–43) bears in western Oklahoma during 2022–2023. Our results provide baseline data on population distribution, abundance, and genetic health of bears in the region and identify factors that may drive human-bear conflicts as the bear population increases in western Oklahoma.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 35.77293937435742° to 37.178660674614676° latitude; -105.09593028457614° to -102.43344614818959° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Bailey A. Kleeberg, Robert Charles Lonsinger, Jennifer R. Adams, Lisette P. Waits, W. Sue Fairbanks. 2025-12-18. Landscape associations and population genetics of a generalist carnivore at a range limit. https://doi.org/10.1371/journal.pone.0334492

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