Hunter Mark Smith welcomes wild birds on to his property, but if he sees a cat, he thinks the "invasive" animal should be considered fair game.

The 48-year-old firefighter from La Crosse has proposed that hunters in Wisconsin make free-roaming domestic cats an "unprotected species" that could be shot at will by anyone with a small-game license.

His proposal will be placed before hunters on April 11 at the Wisconsin Conservation Congress (search) spring hearings in each of the state's 72 counties.

"I get up in the morning and if there's new snow, there's cat tracks under my bird feeder ... I look at them as an invasive species, plain and simple," Smith said.

Smith's proposal has horrified cat lovers, but is seen by others as a way to stop cats from killing wild birds.

University of Wisconsin-Madison wildlife ecology professor Stanley Temple, who trapped more than 100 cats and analyzed their stomach contents during a four-year study, has estimated that between 7.8 million and 219 million birds are killed by rural cats in Wisconsin each year.

"It's obviously a very controversial proposal," Temple said, but added, "I think there really is a basis for having a debate about it."

The Conservation Congress is a five-member elected body whose duty is to advise the Department of Natural Resources (search) and the Legislature on natural resources issues.

DNR attorney Tim Andryk said the vote would simply be "an advisory recommendation" to state lawmakers.

"We (the DNR) don't have authority to regulate domestic animals. Legislation would have to be passed to accomplish this," Andryk said. "You might also have to amend laws relating to abuse of domestic animals."

But Temple said he thinks legislation is not needed. He said the department does have the authority to declare rural cats an unprotected species — because unclaimed cats can be considered nonnative wildlife species like house mice, Norway rats, pigeons and starlings.

"If they are not a pet, if somebody doesn't claim ownership, they become a nonnative wildlife species and not entitled to protection by the state," he said.

Cat enthusiasts Cheryl Balazs, Ted O'Donnell and Adam Bauknecht are trying to organize opposition to Smith's proposal. O'Donnell, a co-owner of MadCat Pet Supplies, recently set up a Web site, dontshootthecat.com, to inform people about it.

O'Donnell said Smith's proposal "is a callous response" to the problem of cats preying on wild birds.

"There's more humane solutions," he said. "We as citizens should step up and solve the problem humanely."

Sheri Carr, senior humane officer at the Dane County Humane Society (search), said the group has not yet taken a position on the proposal, but wants cat owners to abide by their local ordinances and not let their animals roam.

"I would hate to think that tame, owned cats who happen to slip out would be at risk of being deemed a wild, unprotected species," Carr said. "It's a delicate (ecological) balance out there, but does that mean people should be able to shoot their neighbor's cat? Probably not."