‘Humans are inept at caring for baby animals’: why well-fed orphaned bears die in the wild | animals

The orphaned grizzly bear cubs received a generous diet of road kill, watermelon, dog food and snacks donated by the public. Their contact with caregivers was limited to two people. Then, after up to a year of rehabilitation, they returned to their home in the wilds of British Columbia.

“It’s something that makes us feel good: People feel good when the cage opens,” says Dr. Lana M. Ciarniello, a bear specialist who followed Canadian bears in a recent study. There is a perception that bears will thrive in the wild, he says. “The reality is that they are not followed up.”

When Ciarniello studied his fate, he was shocked by his grim findings. All but two of the 12 bears that could be monitored died within a year. Most died before their first winter hibernation. The young bears may have been unintentionally set up for failure, he concluded.

So beefed up that they were 3.5 times the size of typical wild-bred yearlings, they were apparently burdened by their enormous size and unable to meet their caloric needs after their release. Some bears also seemed unafraid of humans, and one female persistently approached mine workers in search of food.

Rescue and release projects often draw strong public appeal, but the study warns that if such work produces bears ill-equipped to navigate the wild, then it remains “a form of sympathetic management” rather than an effective conservation tool.

Teaching a puppy to forage and avoid danger when he has had little or no maternal care (while also preventing him from getting used to human contact) is a big challenge.

Bears have a culture that they learn from their mother over a period of two to three years, says Chris Servheen, co-chair of the North American bear expert team at the International Union for Conservation of Nature (IUCN). “Their mother teaches them what to eat and where to go for food at different times of the year, what to avoid, what to be afraid of,” he says.

“An orphaned animal of any kind, people want to take care of it.” The problem, he says, is that “humans are very inept when it comes to caring for baby animals.”

The general guidelines, which are based on research involving American black bears, suggest that greater body mass gives rehabilitated bears an advantage against predators. A target release weight of approximately 1.5 times that of a free-range bear is recommended.

Ciarniello’s study, funded by the Grizzly Bear Foundation, suggests that going further could be harmful. In the bears he observed, which weighed 3.5 times more than year-old bears raised in the wild, high calorie intake had increased all metrics: body length, chest girth, and neck girth.

“They’re not just fat, plump things. They’re skeletal. Once you have that big structure, you have to maintain it,” Ciarniello says. This led to what she calls a “metabolic trap.”

Two females, released in areas without access to salmon, lost an average of 0.48 kg (1 pound) per day. Even in areas with abundant food sources, the bears could not eat enough.

Giving the bears a little buffer makes sense, says Ciarniello, who is also co-chair of the IUCN human-bear conflict expert team. Too much could be counterproductive.

Experts had previously hypothesized that cutting off contact for two weeks before release would undo the familiarity the bears have developed with humans. However, the bears continued to associate humans with food, even after much longer periods in the wild without contact. Siggi, a woman, spent 59 days in a remote alpine area before encountering mine workers, whose food supplies she raided. Unfazed even by the noise of a helicopter, Siggi died after the incident, one of five bears killed in the human-wildlife conflict.

Of the remaining bears, two were illegally killed and three were killed by wild bears.

Ciarniello says parenting should be done with as little intervention as possible. “We can’t treat them like we’re feeding or raising our dogs. We can’t feed them at 8am and 5pm twice a day by going into their enclosure, even if it’s just one person.”

Rehabilitation projects elsewhere are finding ways to achieve this. Free the Bears, which has sanctuaries in Laos and Cambodia housing Asiatic black bears and sun bears that are being considered for release, uses catapults to deliver food, while a special system picks up high-frequency beeps emitted from the bears’ collars, allowing staff to track their movements. When the animals are to be weighed, honey is dripped onto a scale inside the enclosure to encourage them to climb onto it.

The recovery of orphaned bears is controversial, especially in areas where they are not threatened. Some biologists argue that the money should go elsewhere, to prevent conflicts with humans (and orphaning bears) in the first place.

Others say we need as much information as possible on how to rehabilitate and release bears. “This will be an essential conservation tool to employ, especially for species like sun bears that don’t look good,” says Dr. Zachary David, director of the Free the Bears research program.

The Grizzly Bear Foundation says the findings, which will also form a best practices report, “will ensure that science informs future policies and practices in British Columbia, where rewilding is currently possible, and in other jurisdictions considering what options should be available.”

Brown bears (of which grizzlies are a subspecies) are not globally endangered, but there are many small, isolated populations that are threatened, and Ciarniello hopes his work will inform efforts to protect populations in Europe and Asia. “I’m worried those bears will disappear if we can’t figure this out.”

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