Five-year study shows complex signs of elephant adaptation
After decades spent in tourist camps and circuses, African elephants that have been released into the wild are behaving, in many ways, like elephants that have never been captive.
A new study offers cautious evidence that elephants can find many wild behaviors. Eleven free-living elephants in South African reserves showed rates of vigilance, confrontation and self-directed touching broadly similar to those of wild elephants, researchers report July 29. PLOS One. But the stress measurements revealed a more complex situation, suggesting the need for further work to determine whether the animals are well adapted.
“It is encouraging that despite prolonged periods of captivity, elephants are indeed able to ‘readapt’ to natural conditions, if given the opportunity,” says Sanjeeta Sharma Pokharel, an elephant biologist at Kyoto University in Japan, who was not involved in the work.
Around the world, more than 15,000 Asian and African elephants are kept in captivityoften in zoos and temples, in tourist and forest camps, as well as in circuses and private establishments. Many suffer from osteoarthritis, reduced reproductive success And shorter lifespans.
Animal protection groups have long called for better living conditions and more humane treatment of these elephants. But there is a shift in sentiment underway toward the idea of giving captive elephants the chance to live more naturally, Pokharel says.
One option is to return these animals to the wild, either through immediate release or a gradual transition. Over the years, researchers have assessed the fate of ex-captives.
A recent study in Sri Lanka found that groups of orphaned Asian elephants released into the wild acclimatized quicklyshowing rapid recovery from stress. A study in Botswana showed that after their release, newly released African elephants adjusted their movement patterns in response to seasonal signals.
In the new study, researchers recorded the behaviors of 11 African elephants (African Loxodont) on three fenced South African reserves and compared them to sightings of wild elephants in a fourth, much larger, open reserve system. The team documented how often the elephants touched or brushed each other’s faces, waved their trunks or swung their feet, for example. These behaviors can be used to catalog moments of uncertainty, unease, irritation, or alertness.
Ex-captive elephants often exhibited these behaviors at similar frequencies to wild elephants. But when it came to attentive behavior, rewilding pachyderms assessed and gauged their surroundings less often than wild individuals. That’s likely because the animals didn’t need to practice these skills in captivity, says Tenisha Roos, a researcher at the Elephant Reintegration Trust in South Africa.
Overall, elephants seem to adapt to nature, Roos says, despite their varied individual personalities and past traumas. Rehabilitation works if animals are released in groups and there are existing elephants at the release site to potentially join and learn from, she says.
But not all captive elephants are suitable for rewilding, and many landscapes may not be suitable for their return. Think about fragmented forests and areas already plagued by human-elephant conflict.
But where rewilding opportunities exist, Pokharel also suggests monitoring the physiology of rehabilitated elephants to better understand how the animals are coping. Roos and his colleagues previously measured levels of a stress biomarker and found that these were higher in several rewilded individuals. But Pokharel suggests the team needs more robust sampling as well as tracking other fitness indicators such as reproductive hormones to fully assess the program’s success.