A recent study tracking orphaned grizzly bear cubs released in British Columbia found that most did not survive their first year in the wild. Of the 12 monitored bears, all but two died within a year, with many perishing before their first winter hibernation.
Dr Lana M Ciarniello, a bear specialist involved in the study, noted that the bears were significantly larger than their wild counterparts, having been fed a generous diet during rehabilitation. This increased size may have created a "metabolic trap," making it difficult for them to meet their calorie needs in the wild.
The study also observed that some rehabilitated bears appeared unafraid of humans, with one persistently approaching mine workers for food. This behaviour led to the death of five bears in human-wildwildlife conflict, while others were killed illegally or by wild bears.
Experts suggest that while rescue and release projects are popular, they may not be effective conservation tools if bears are not adequately prepared for the wild. The findings will inform future policy and practice in British Columbia and other regions considering rewilding efforts.