Efforts to rehabilitate and release orphaned grizzly bears face significant challenges, according to recent research highlighting the complexity of preparing young bears for survival in the wild. The study emphasizes that while public support for rescue programs is strong, these initiatives may fall short in producing bears that are adequately equipped to thrive independently, raising questions about their effectiveness as conservation tools.
Grizzly bears learn essential survival skills from their mothers over a period of two to three years, including what to eat, where to find seasonal food sources, and which threats to avoid, explained Chris Servheen, co-chair of the International Union for Conservation Nature’s (IUCN) North American bears expert team. Orphaned bears, lacking this cultural knowledge, often struggle to develop the necessary behaviors to navigate their environment safely. Despite good intentions, humans are generally unable to replicate this learning process adequately, Servheen noted.
Current rehabilitation guidelines suggest releasing bears at a body weight approximately 1.5 times that of their wild-reared counterparts to provide them an advantage against predators. However, recent findings by researcher Ciarniello, funded by the Grizzly Bear Foundation, indicate that some rehabilitated bears were released at weights up to 3.5 times greater than wild yearlings. This elevated weight appeared to include not only fat but increased skeletal growth as well, which introduced new challenges related to maintaining such a large physical frame once in the wild.
The research observed two female bears released in areas without access to salmon losing an average of 0.48 kilograms per day. Even in habitats with plentiful food, the bears were unable to consume enough to sustain their body mass. These results suggest that simply increasing weight before release may not translate into survival benefits and could instead impose additional metabolic burdens.
Another significant concern is the bears’ continued association of humans with food, even after extended periods in the wild without human contact. This persistent behavior undermines the goal of fostering natural wariness, increasing the risk of dangerous human-bear interactions. Ciarniello emphasized the importance of maintaining a hands-off approach during rehabilitation to minimize human imprinting, advising against regular feeding schedules or frequent enclosure visits.
Some rehabilitation programs are adopting innovative methods to reduce human contact, such as using catapults to deliver food or employing remote monitoring technologies that encourage bears to weigh themselves voluntarily without direct handling. These approaches aim to support the bears’ transition to the wild while limiting habituation to people.
The rewilding of orphaned bears remains a subject of debate, particularly in regions where bear populations are stable. Some biologists argue that resources would be better allocated toward conflict prevention and habitat protection to reduce the number of orphaned cubs. Others call for expanded research to improve rehabilitation strategies and inform future policies.
The Grizzly Bear Foundation underscored that these new findings will guide conservation efforts in British Columbia and beyond. While brown bears, including grizzlies, are not globally endangered, isolated populations face threats from habitat loss and human activities. Ciarniello expressed concern for vulnerable groups in Europe and Asia, stressing the need to refine rehabilitation techniques to prevent further population declines.
Notably, data from the study indicate high mortality among rehabilitated bears after release, with 10 of 12 individuals dying within their first year in the wild, many before their initial winter hibernation, underscoring the urgent challenges involved in successful bear reintroduction programs.