Conservation of Threatened Canada-USA Trans-border Grizzly Bears Linked to Comprehensive Conflict Reduction

Mortality resulting from human–wildlife conflicts affects wildlife populations globally. Since 2004, we have been researching conservation issues and implementing a comprehensive program to reduce human–bear conflicts (Ursus spp.; HBC) for 3 small, fragmented, and threatened grizzly bear (U. arctos) populations in the trans-border region of southwest Canada and northwest USA. We explored the temporal and spatial patterns of conflict mortality and found that HBC contributed significantly to the threatened status of these populations by causing decline, fragmentation, and decreased habitat effectiveness. Our program to reduce HBCs primarily included strategic private lands purchased to reduce human density in wildlife corridors, the reduction of bear attractants where human settlement and agriculture exists, and the nonlethal management of conflict bears. Attractant management strategies encompassed public education, cost-share electric fencing, bear-resistant garbage containers, and deadstock containment. We taught bear safety courses and bear spray training to increase tolerance and give people tools to avoid negative encounters with bears. We radio-collared and used nonlethal management on potential conflict bears and have a ~75% success rate in that the bear was alive and out of conflict situations over the life of the radio-collar. We identified important backcountry grizzly bear foraging habitat for motorized access control to reduce conflict and mortality and provide habitat security to reproductive females. Ongoing monitoring has demonstrated that our comprehensive HBC program has resulted in a significant reduction in human-caused mortality, increased inter-population connectivity, and improved habitat effectiveness. Several challenges remain, however, including an increase in the numbers of young grizzly bears living adjacent to agricultural areas. Herein we discuss strategies for how to integrate conservation vision into future HBC reduction programs

Grizzly Bear Population Vital Rates and Trend in the Northern Continental Divide Ecosystem, Montana

We estimated grizzly bear (Ursus arctos) population vital rates and trend for the Northern Continental Divide Ecosystem (NCDE), Montana, between 2004 and 2009 by following radio-collared females and observing their fate and reproductive performance. Our estimates of dependent cub and yearling survival were 0.612 (95% CI = 0.300–0.818) and 0.682 (95% CI = 0.258–0.898). Our estimates of subadult and adult female survival were 0.852 (95% CI = 0.628–0.951) and 0.952 (95% CI = 0.892– 0.980). From visual observations, we estimated a mean litter size of 2.00 cubs/litter. Accounting for cub mortality prior to the first observations of litters in spring, our adjusted mean litter size was 2.27 cubs/litter. We estimated the probabilities of females transitioning from one reproductive state to another between years. Using the stable state probability of 0.322 (95% CI = 0.262–0.382) for females with cub litters, our adjusted fecundity estimate (mx) was 0.367 (95% CI = 0.273–0.461). Using our derived rates, we estimated that the population grew at a mean annual rate of approximately 3% (λ = 1.0306, 95% CI = 0.928–1.102), and 71.5% of 10,000 Monte Carlo simulations produced estimates of λ \u3e 1.0. Our results indicate an increasing population trend of grizzly bears in the NCDE. Coupled with concurrent studies of population size, we estimate that over 1,000 grizzly bears reside in and adjacent to this recovery area. We suggest that monitoring of population trend and other vital rates using radioed females be continued

Grizzly Bear Population Vital Rates and Trend in the Northern Continental Divide Ecosystem, Montana

We estimated grizzly bear (Ursus arctos) population vital rates and trend for the Northern Continental Divide Ecosystem (NCDE), Montana, between 2004 and 2009 by following radio-collared females and observing their fate and reproductive performance. Our estimates of dependent cub and yearling survival were 0.612 (95% CI = 0.300–0.818) and 0.682 (95% CI = 0.258–0.898). Our estimates of subadult and adult female survival were 0.852 (95% CI = 0.628–0.951) and 0.952 (95% CI = 0.892– 0.980). From visual observations, we estimated a mean litter size of 2.00 cubs/litter. Accounting for cub mortality prior to the first observations of litters in spring, our adjusted mean litter size was 2.27 cubs/litter. We estimated the probabilities of females transitioning from one reproductive state to another between years. Using the stable state probability of 0.322 (95% CI = 0.262–0.382) for females with cub litters, our adjusted fecundity estimate (mx) was 0.367 (95% CI = 0.273–0.461). Using our derived rates, we estimated that the population grew at a mean annual rate of approximately 3% (λ = 1.0306, 95% CI = 0.928–1.102), and 71.5% of 10,000 Monte Carlo simulations produced estimates of λ \u3e 1.0. Our results indicate an increasing population trend of grizzly bears in the NCDE. Coupled with concurrent studies of population size, we estimate that over 1,000 grizzly bears reside in and adjacent to this recovery area. We suggest that monitoring of population trend and other vital rates using radioed females be continued