DETROIT, Mich. (AP) -- With thousands of feral pigs threatening farms and native species, the Michigan Department of Natural Resources and Environment has declared the bristly swine an invasive species and given the Legislature until July 8 to come up with regulations on breeding and confining the tusked animals or ownership of them will be banned.
The agency estimates there 3,000 to 5,000 feral pigs in more than 65 of Michigan's 83 counties. Many of the animals are the offspring of imported Russian or Eurasian boars that escaped from area game preserves, The Detroit News reported Saturday.
Feral pigs eat anything and everything, including endangered wild plants, the eggs of game birds, young deer or lambs, reptiles and farm crops. Nationwide, the U.S. Department of Agriculture estimates they cause about $800 million in damage each year to agriculture. The pigs also can carry diseases including bovine herpes virus, swine fever, foot and mouth disease, influenza, anthrax and swinepox virus.
"They will really rip up a farmer's fields," DNRE spokeswoman Mary Detloff said. "Overnight, they can destroy acres of corn and wheat. They dig wallows 3-feet deep and 5-feet wide, which are a real danger to farming equipment."
The agency has essentially approved shooting the animals on sight.
"Basically, our policy is shoot first and ask questions later," Detloff said.
Outgoing DNRE Director Rebecca Humphries signed an order declaring the pigs an invasive species in December and set the deadline for them to be banned unless the Legislature acts.
Russian boars average about 100 to 200 pounds, but if they interbreed with domestic hogs their offspring can grow up to 300 pounds. Females can produce two litters of eight to 10 piglets a year.
The majority of the 289 swine sightings since 2001 have been in the Lower Peninsula, with the highest numbers in Gratiot, Midland, Roscommon and Mecosta counties.
But game preserve owners say the numbers are exaggerated.
"Feral hogs do exist, but there are so few incidents of them in the wild," said Salvatore D. Palombo, owner of the 320-acre County Line Game Ranch in Beaverton and president of the Michigan Animal Farmers Association.
Palombo admitted some pigs may have escaped over the years, but none from his ranch.
"I have a double fence around the ranch plus a 10-foot wide road in the middle," said Palombo, who keeps about 40 hogs for breeding. "If a hog were to escape, it would be the same as if I set fire to a $500 bill."
"I've talked with hunters from all over the state, and I've never met one that's seen one wild in the woods," added Ron McKendrick, who owns the 320-acre Renegade Ranch in Cheboygan. "I'm not saying they're not there, but I think the numbers are a lie."
But Ric Buikema, 37, and his father, Ken, 62, said they have killed nine feral hogs in western Michigan since July.
"They are nasty looking animals," Buikema said.
State Sen. Tom Casperson, R-Escanaba, said some legislators want to regulate the swine preserves rather than close them down.
"If we shut them down, we'll be taking everything away from them," said Casperson, chairman of the Senate Natural Resources and Environmental Policy Committee. "I've been told there's a problem, but so far, I really haven't seen a lot of evidence of it."
Casperson said lawmakers handled a similar situation with game preserves for deer and elk.
"We came up with regulations about raising and confining the animals," he said. "I see a real similarity between what we did for deer and elk and what we can do for swine."