A dog was killed Tuesday near Duluth’s Brighton Beach, and authorities said the evidence suggests a wolf may be responsible.

A medium-sized golden retriever mix was walking off-leash on a trail with its owner Tuesday near the park in far eastern Duluth when the dog was killed by another canine that authorities suspect was a wolf, said Brent Speldrich, a conservation officer with the Minnesota Department of Natural Resources.

The owner didn’t see what happened, but tracks of another canine were found near the dog, he said.

Wolf interactions in the area are common occurrences, Speldrich said.

“We live in a wolf range,” he said, noting this would be the second incident in recent weeks in which a wolf killed a dog in the area.

Speldrich said Duluth residents should keep dogs leashed and should accompany dogs outside at night, keeping pets close. City law requires dogs to be leashed.

Both wolves and coyotes sometimes kill dogs, said Mike Schrage, wildlife biologist for the Fond du Lac Band of Lake Superior Chippewa. He said there are a couple of reasons why a wolf or coyote might kill a dog.

“They’re natural competitors. They’re all canines,” he said. “They’re fairly close in size, and there’s natural competition there. In the case of wolves, sometimes they’re hungry. This has not been a particularly easy winter for wolves to kill deer. Snow depths are not that deep.”

A wolf that attacks a dog is not necessarily unhealthy, Schrage said.

“Healthy wolves do it all the time,” he said.

Federal trappers for the U.S. Department of Agriculture who respond to complaints of suspected wolf attacks across northern Minnesota received 220 complaints in 2015, both from livestock owners and pet owners, said John Hart, district supervisor of USDA wildlife services in Grand Rapids.

Of those, only about half were verified as wolf attacks, including 18 attacks on dogs across the region. Federal trappers trapped and killed 220 wolves near where those verified attacks took place. The trapping is allowed under the federal Endangered Species Act because wolves in Minnesota are officially listed as threatened, not endangered.

There has been no sport trapping or hunting season in Minnesota since December 2014 when a federal judge restored federal protections, making it illegal for citizens to kill wolves.

Speldrich said complaints about animals being killed by wolves aren’t on the rise, but that news about such events are heard more often because of social media.

News Tribune reporter Sam Cook contributed to this report.