PORTLAND — Wolf hybrids, animals that are a cross between wolves and dogs, will vanish from Maine over time if a new state law works as designed.

The law prohibits people from acquiring wolf hybrids without a special wildlife-in-captivity permit, and it requires current owners to have the animals neutered.

Supporters of the law say wolf hybrids have been responsible for numerous brutal attacks around the country, particularly against children. Wolf hybrids are predatory and should be in the wild, said state Sen. David Trahan, who sponsored the bill that outlaws them.

“Wolf hybrids are not pets,” he said. “Would people consider bringing a coyote or mountain lion into their home crossed with another cat or another dog?”

Jim Doughty, who operates a wolf hybrid refuge in Bristol that is not affected by the law because it is already licensed by the state, said people who want the animals will skirt the law by licensing them as shepherd or huskie mixes rather than wolf hybrids. The law is misguided and unfairly brands the animals, said Doughty, who keeps four wolf hybrids at the Wolf Ledge Refuge.

“Any animal, no matter whether it’s a pure wolf or a Chihuahua or a pug or anything else, depends on the person and how they raise it,” he said. “It’s the same thing with your kids. If you’re abusive toward your kids, they’re not going to be so good. If you work with them, they’ll be great.”

Maine legislators last spring passed emergency legislation aimed at getting rid of wolf hybrids, which are also known as wolf dogs or wolf-dog hybrids. Trahan introduced the legislation after people in his district raised concerns about Doughty’s wolf hybrid refuge, which he opened last year and is licensed to have up to 20 of the animals.

Wolf hybrids have been responsible for at least 84 attacks that have either maimed or killed people in the past three decades, said Merritt Clifton, editor of Animal People, an animal protection newspaper based in Washington state. Of those attacks, 69 involved children and 19 resulted in deaths.

Clifton, who has tracked dog attacks nationally for decades, said that’s a huge number considering wolf dogs make up only an estimated 1/100th of 1 percent of all dogs in the U.S.

Under Maine’s law, people are prohibited from acquiring wolf dogs unless they have a permit issued by the Department of Inland Fisheries and Wildlife to possess wildlife in captivity.

The Department of Agriculture is charged with compiling a list of wolf hybrid owners from towns were the animals are licensed. When people license their animals, they have to provide a record of a rabies vaccination, which must include the breed of animal and be signed by a veterinarian.

Nobody’s sure how many wolf hybrids are in Maine, but state officials should get an idea soon when it starts compiling the list of owners.

“I expect that list will be at its highest this winter, and if people follow the law it will slowly start to decline,” said Don Hoenig, Maine’s state veterinarian.

Maine joins a growing number of states that have passed laws banning the animals. Forty states effectively forbid the ownership, breeding and importation of wolf dogs, while others impose some form of regulation upon ownership, according to the Illinois-based National Wolfdog Alliance.

Beth Duman, who has studied wolves for nearly 40 years and testified last spring on Maine’s law, said the number of wolf hybrids in her home state of Michigan has dwindled to nearly nothing since the state passed a law prohibiting them about a decade ago, she said. Duman is a wolf educator who has written a book about wolves and wolf hybrids in the Great Lakes region.

“We have no more hybrids advertised,” she said. “They’re not coming into the pounds. It’s a made a big difference.”

In Maine, the controversy continues in Bristol over Doughty’s refuge, where he takes in wolf hybrids from people who don’t want or can’t take care of them. Last month, one of Doughty’s animals, Luna, showed up in a neighbor’s backyard after running off when somebody inadvertently left Doughty’s front door open.

“I heard my chickens going crazy and I looked out and it was attacking one of my chickens, shaking it, feather flying everywhere,” said Stacey Simmons, who helped organize a petition last year trying to prevent the refuge from opening.

Simmons came out on her back deck, screamed at the animal, threw a rug at it and grabbed her golden retriever and put it inside. Luna wasn’t fazed by anything and eventually retreated to the woods with the chicken in her mouth, Simmons said. The chicken — bloodied and distraught — re-appeared the next day.

But the episode shows that wolf hybrids have no business being in a neighborhood, she said.

“What’s going to be next? A kid being attacked?” she said.

Doughty doesn’t consider wolf hybrids to be dangerous, although he said he wouldn’t recommend them for people with small children or who don’t have the space to let the animals run.

And he doesn’t think the law will eliminate wolf dogs from Maine.

“Owners are going to list it as another dog,” he said. “The vet might know it and everybody else might know it, but nobody’s going to say a word.”