R. Eastridge M.J. Hooker J. D. Clark 2010 <p><span>We live-trapped American black bears (</span><i>Ursus americanus</i><span>) and sampled DNA from hair at White River National Wildlife Refuge, Arkansas, USA, to estimate annual population size (</span><i>N</i><span>), growth (λ), and density. We estimated </span><i>N</i><span> and λ with open population models, based on live-trapping data collected from 1998 through 2006, and robust design models for genotyped hair samples collected from 2004 through 2007. Population growth was weakly negative (i.e., 95% CI included 1.0) for males (0.901, 95% CI  =  0.645–1.156) and strongly negative (i.e., 95% CI excluded 1.0) for females (0.846, 95% CI  =  0.711–0.981), based on live-trapping data, with </span><i>N</i><span> from 1999 to 2006 ranging from 94.1 (95% CI  =  70.3–137.1) to 45.2 (95% CI  =  27.1–109.3), respectively, for males and from 151.4 (95% CI  =  127.6–185.8) to 47.1 (95% CI  =  24.4–140.4), respectively, for females. Likewise, mean annual λ based on hair-sampling data was weakly negative for males (0.742, 95% CI  =  0.043–1.441) and strongly negative for females (0.782, 95% CI  =  0.661–0.903), with abundance estimates from 2004 to 2007 ranging from 29.1 (95% CI  =  21.2–65.8) to 11.9 (95% CI  =  11.0–26.9), respectively, for males and from 54.4 (95% CI  =  44.3–77.1) to 27.4 (95% CI  = 24.9–36.6), respectively, for females. We attribute the decline in the number of females in this isolated population to a decrease in survival caused by a past translocation program and by hunting adjacent to the refuge. We suggest that managers restructure the quota-based harvest limits until these growth rates recover.</span></p> application/pdf 10.2193/2009-529 en Wildlife Society Effects of exploitation on black bear populations at White River National Wildlife Refuge article