Are wolf populations in Yellowstone leveling out?
A new report shows a declining population of wolves in Yellowstone National Park, but a lead author describes it as a result of the predators coming into balance with their environment.
“The number of wolves are here that can be supported by prey,” said Doug Smith, Yellowstone Senior Wildlife Biologist and leader of the Yellowstone Wolf Project.
The most recent annual report provides insight into the park’s wolf population as of the end of 2012. Wolf numbers then stood at at least 83 wolves in 10 packs. It’s a 15 percent drop from the previous three years and a 50 percent population drop from 2007, after which wolves failed to bounce back from a disease outbreak. Wolves were originally reintroduced to the park in 1995.
“In the early days, there were just a lot more elk, so that produced a lot more wolves,” Smith said. “And so those days are kind of over and so we have fewer wolves in the park as a result.”
Smith is careful to point out wolves were not solely responsible for the decline in elk. Mountain lions have found their way into the park recently and grizzly populations are on the rise. Montanans were hunting more elk on the park’s northern boundary. Smith also says there is increasing evidence showing elk decline due to climate related factors.
With fewer elk, wolves in the park have started seeking other sources of food, including scavenging the carcasses of bison and moose. Overall, Smith said the leading cause of wolf deaths in the park today is other wolves.
“Wolves go looking for food, which means they trespass on other wolves territories and because they’re territorial, they fight back,” he said.
Meanwhile, populations in Montana also seem to be reaching a state of balance, at least in regions where they have been for awhile.
“We don’t have that sense where they haven’t expanded into new territories,” said Montana Fish, Wildlife and Parks Spokesman Ron Aasheim. “And we know there are places in Montana that can support wolves and it’s only gonna be a matter of time for them to move into those niches.”
FWP predicted there was a minimum of 625 wolves in the state at the end of 2012, a decrease of four percent from the previous year. Aasheim said 2013 numbers should be available in about a month.
So far in the 2013/2014 hunting season, Montana hunters have killed 123 wolves. Another 47 were killed by trappers. The trapping season runs through the end of February and hunting runs through March 15.
Aasheim said the state wants to continue to manage wolves in a way that satisfies landowner tolerance and minimizes impact on big game populations.
“We haven’t had enough experience yet to know where we’re gonna need to be to reach that balance. That’s really the art here, and the science,” he said.