Minnesota’s wolf population remains generally stable, although wolves are having to roam farther to find their favorite food, the Department of Natural Resources reported Monday.

The DNR said the 2015 survey showed an estimated 2,221 wolves in 374 packs across the northern half of the state.

That’s down about 8 percent from the 2014 estimate but close enough to call stable, the agency noted.

“Results from the 2015 wolf survey demonstrate that the wolf population remains well established across northern and central Minnesota,” Dan Stark, large carnivore specialist for the DNR, said in a news release.

DNR officials said that the average number of wolves in a pack is increasing, from 4.4 in 2014 to 5.1 this year, and that each pack’s hunting territory is increasing - probably a sign that wolves are having to travel farther because there are fewer deer in the woods than a few years ago. Deer are by far the major food source for wolves, and deer numbers are down across most of the wolf range.

Territories for each pack jumped from an average of 58 square miles in 2014 to about 73 square miles last winter.

“When prey declines, wolves must eventually readjust to the new conditions, which typically means fewer packs and each utilizing a larger territory to meet nutritional demands and sustain a competitive pack size,” John Erb, DNR wolf research scientist, said in a news release.

DNR officials noted that wolves did the same things in the late 1990s after deer numbers dropped because of extreme snow and cold winters.

It’s the third straight winter with similar wolf numbers, the DNR noted. Their numbers are sometimes questioned by wolf supporters, who say wolf numbers are down, and by many deer hunters who insist there are far more wolves in the woods than the DNR estimates.

The population survey is conducted in winter near the low point of the annual population cycle. After new pups are born each spring, the wolf population typically doubles, though many pups do not survive to the following winter.

Minnesota’s wolf population remains above the state’s minimum management goal of at least 1,600 wolves, and is above the federal recovery goal for Minnesota wolf numbers of 1,251 to 1,400.

Wisconsin DNR officials estimated 746 wolves in their 2015 winter survey, up 12 percent from 2014.

Minnesota wolves were both hunted and trapped from 2012-2014, which reduced their overall numbers. But those seasons are now on hold after a December 2014 court ruling that placed the animals back under federal Endangered Species Act protections in Minnesota, Wisconsin and Michigan.

That means there will be no hunting or trapping of wolves in those states this year, and that it is a federal offense to kill a wolf in most circumstances.

It remains unclear if or when states will regain wolf management. Legislation has been introduced in Congress that would override the court decision and restore state control of wolves. So far those bills have not advanced.

A total of 272 wolves were shot and trapped during limited seasons in Minnesota last year, more than the DNR's target harvest of 250.

Collette Adkins, a Minnesota-based attorney and biologist for the Center for Biological Diversity, said current wolf numbers remain well below the numbers before trapping and hunting were allowed from 2012-2014.

Minnesota's estimated wolf population was as high as 3,000 in 2008.

“Today’s population estimate reflects the 25 percent drop from sport hunting and increased depredation control that occurred after wolves lost protections under the Endangered Species Act,” Adkins told the News Tribune. “With state managers dead-set on killing wolves, I’m so glad wolves have regained federal protection. Hopefully now wolf numbers will begin to rebound so wolves can continue to play their important ecological role in Minnesota.”

An official from the Minnesota Deer Hunters Association did not immediately return a request to comment on the wolf population results.