New research may have found the solution for burgeoning wolf populations, at least in one corner of North America. Presenting their findings in a recent article in the peer-reviewed journal PeerJ, researchers from the University of British Columbia and the University of Alberta have found that killing moose makes the number of nearby wolves decrease.
But wait, there’s more. Not only will the wolves decrease, but mountain caribou numbers will increase. All this without having to kill the wolves themselves—or suffer the hassle of bureaucracy and animal rights activists.
Researchers followed the three species for more than a decade through the remote forests of southern British Columbia. The endangered mountain caribou has been found there since time immemorial, but moose and wolves are newcomers to the area. Native Americans in the region didn’t even have a word for moose, but the ungulates are now found throughout the caribou’s haunts. Hot on their trail were the wolves, which quickly took to hunting both prey species.
There were several causes for this. Changes in vegetation opened the caribou’s locale to moose feeding. As they moved in, wolves naturally followed their food source. Add in the pressure from hunters on both species and it’s easy to see why they flooded into the more remote region.
As with any non-native introduction, the native species began to suffer. Moose were accustomed to the wolves’ tactics, but the caribou were not. Their populations plummeted as a result, while moose numbers doubled in the area from 1994 to 2003.
The researchers made use of a change in hunting regulations to conduct surveys on how to to best help the caribou. In 2003 British Columbia increased the number of moose-hunting permits tenfold in part of the Columbia Mountains. The researchers measured the changes in this area versus a control area where the moose quota wasn’t raised.
What they found was highly suggestive. Moose numbers inside the test zone dropped by as much as 82 percent by 2014, down from 1,700 to roughly 300. Wolves decreased, too—their dispersal rate increased two and a half times, several starved, and the number of pups decreased. More wolves were killed by humans in the test area, whether by vehicles, trapping, or hunting, than in the control area, too.
Adult caribou survival rates increased from 78 to 88 percent over the same time. Of the three subpopulations inside the test area, the largest was even able to stabilize from the wolf predations.
The two caribou subpopulations in the control area continued to decline, and fewer wolves were killed by humans there—roughly 52 percent less. Even though logging restrictions and limits on activities like snowmobiling have been put in place to protect the mountain caribou, it seems that killing more moose is the key to saving this unique subspecies.
“The band-aid solution is killing wolves, but that’s been treating the symptom,” Robert Serrouya, a biologist at the University of Alberta and leader of the study, told the New York Times. “We’re trying to deal with the cause.”