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Protected areas may provide insufficient protection for carnivores such as bears (Ursidae) with large home ranges and extensive seasonal movements. Even in protected areas, harvest can be the main cause of mortality if parks are small or individuals live close to the boundary. At >7,600 km2, Algonquin Provincial Park (APP) is the largest protected area in southern Ontario, Canada, yet wolves (Canis lycaon c.f.) experienced increased mortality when leaving APP to hunt white-tailed deer (Odocoileus virginianus). American black bears (Ursus americanus; hereafter, bears) also undertake seasonal movements, and may incur increased risk of harvest related mortality if they leave the park. We fitted 72 bears with Global Positioning System or Very High Frequency radiocollars during 2006–2014 to determine overall and cause-specific mortality rates, and whether risk of mortality changed when bears left APP or during years of low natural food availability. Further, we compared the abundance of resident bears with harvest rates in Wildlife Management Units (WMUs) surrounding APP to determine whether harvest was higher in areas surrounding the park compared with WMUs farther from the park boundary. Hazard analysis showed annual mortality for radiocollared bears in APP was 15%. Harvest mortality was double that of all other causes combined. Bears were 7 times more likely to die outside the park. Years of lower natural food availability inside the park, or higher red oak (Quercus rubra) availability outside the park did not significantly alter the risk of mortality. Male bears were 6 times more likely to be harvested than females, and 4 times more likely to die from other causes. High harvests of bears in WMUs near APP contrasted with low abundance of resident bears, suggesting that APP acts as a source population for harvest that occurs near park boundaries. Meaningful maintenance of the integrity of bear populations in protected areas should be undertaken at the landscape scale.

Polar bears (Ursus maritimus) are managed by the 5 nations where they occur (Canada, Greenland/Denmark, Norway, Russia, United States) using discrete subpopulations. In Canada, polar bears are harvested throughout their range, and several subpopulations are managed by more than one jurisdiction; therefore, recent management focused on ensuring sustainable polar bear harvests. Consequently, the subpopulation from which harvested bears are removed and the geographic boundaries of that subpopulation must be correctly identified. However, boundaries of the Southern Hudson Bay (SH) subpopulation have not been verified using satellite radio-telemetry data. Sea ice duration has already declined in Hudson Bay and James Bay, and both the duration and distribution of sea ice are predicted to decline greatly in the next century; therefore, it is important to document current habitat use patterns to assess the potential impacts of climate change. We used a probabilistic approach to describe the utilization d...

Polar bears (Ursus maritimus) occupy remote regions that are characterized by harsh weather and limited access. Polar bear populations can only persist where temporal and spatial availability of sea ice provides adequate access to their marine mammal prey. Observed declines in sea ice availability will continue as long as greenhouse gas concentrations rise. At the same time, human intrusion and pollution levels in the Arctic are expected to increase. A circumpolar understanding of the cumulative impacts of current and future stressors is lacking, long-term trends are known from only a few subpopulations, and there is no globally coordinated effort to monitor effects of stressors. Here, we describe a framework for an integrated circumpolar monitoring plan to detect ongoing patterns, predict future trends, and identify the most vulnerable polar bear subpopulations. We recommend strategies for monitoring subpopulation abundance and trends, reproduction, survival, ecosystem change, human-caused morta...

Minimizing conflicts with humans is a necessary component of the management of American black bears (Ursus americanus) across most of their range. The number of complaints about conflicts with black bears is commonly used to infer trends in the actual frequency or severity of human–bear conflict, and even trends in bear population size. However, the number of complaints received by management agencies is a function of both the frequency of and the reporting rate for conflicts, and the reporting rate may change over time. We tested for effects of food availability, numbers of bears harvested, and management regime changes on 3 measures of human–bear conflict: (1) public complaints, (2) traps set to capture bears involved in conflicts, and (3) bears killed in defense of property in Parry Sound, Ontario, Canada, 1992–2008. All measures of human–bear conflict were inversely related to food availability. Complaints increased following a controversial change in management (cancellation of the spring hu...

American black bear (Ursus americanus) population dynamics are most sensitive to survival of adult females. To ensure that harvest is sustainable, harvest should be skewed to males. In addition, in jurisdictions with a spring harvest, lactating females should not be harvested. Hunting over bait provides hunters the opportunity to observe bears, yet many hunters have difficulty identifying the sex of bears at bait sites. We evaluated the use of suspended baits to determine whether this technique could help hunters correctly distinguish male from female black bears. We also evaluated hunter knowledge of black bears and hunter familiarity with hunting regulations to determine whether these influenced harvest. The proportion of female black bears harvested at suspended or traditional ground bait sites was similar; however, hunters did not always give bears the opportunity to stand at suspended baits. The suspended bait technique shows promise and should be explored further in a larger study. Using th...

The objective of this study was to define the conditions under which the body mass of polar bears (Ursus maritimus) can be estimated by morphometry with acceptable accuracy (high precision and low bias). Morphometric and body mass values from 563 polar bears captured and handled in southern Hudson Bay during 1984–86 and 2000–03 were analyzed to determine the effects of sample size and time on the accuracy of estimated body mass (EBM) and to determine the effect of using EBM versus observed body mass (OBM) to calculate body condition index (BCI) values. When sample size was small (≤25), variation around the difference between OBM and EBM was large. However, precision improved markedly with increasing sample size, stabilizing within approximately 3% for sample sizes ≥100. Morphometric–body mass relationships developed for southern Hudson Bay polar bears in the mid-1980s consistently overestimated body masses of bears handled since 2000 by approximately 4%, suggesting relationships within the popula...

Managers of American black bears (Ursus americanus) must maintain populations to ensure viability and opportunities for sport harvest, and minimize human-bear conflict (HBC). Harvest is a cost-effective management tool in most jurisdictions, and intuitively it seems that with fewer bears, there should be fewer conflicts. Therefore, managers may attempt to achieve both objectives by manipulating the harvest. Further, because data describing harvest and HBC are frequently collected, managers sometimes infer changes in population status from trends in harvest and HBC. However, evidence that larger harvests reduce HBC is lacking, and changes in harvest metrics and the frequency of HBC may be independent of bear density. Understanding relationships among food availability, hunter effort, harvest, and HBC could help managers avoid making invalid inferences about population status from data describing harvest and HBC, and evaluate whether management actions are having intended results. We investigated relationships among food availability, HBC, and harvest at landscape scales in Ontario, Canada, 2004-2011. We hypothesized that HBC and harvest would be negatively correlated with food availability; that HBC would be negatively correlated with prior harvest; and that harvest would be positively correlated with number of hunters. We used Spearman rank correlation to test hypotheses. Human-bear conflict was negatively correlated with food availability across Ontario, and in the 2 administrative regions where food availability varied synchronously. Total harvest and the proportion of females in the harvest were negatively correlated with food availability across Ontario and in one region. Human-bear conflict was not correlated with prior harvests, providing no evidence that larger harvests reduced subsequent HBC. Given the variation in natural foods, harvest is unlikely to prevent elevated levels of HBC in years of food shortage unless it maintains bears at low densities—an objective that might conflict with maintaining viable populations and providing opportunities for sport harvest.