SALEM, Ore. (AP) — Washington state is monitoring the wild pig populations in Oregon, where the fish and wildlife department has ordered farmers to determine the size of the destructive pig populations on their land and get rid of them.
The Oregon Department of Fish and Wildlife knows feral pigs are a problem. As an invasive species, they threaten crops and cause headaches for farmers.
The state doesn't yet know how big of a problem. That's because most feral pigs in the state live in the low-precipitation private land. >>> Map of feral pig's range in Oregon
But they're inching closer to the high-value crop land, and neighboring states in the Pacific Northwest are worried.
Feral pigs, like most problems in Oregon, get blamed on California. The pigs are game mammals in the state, meaning hunters have to get tags to shoot them. In the meantime, they root up cropland, destroy hillsides and generally wreak havoc on the environment.
A bill passed last year in Oregon requires landowners to trap or shoot any feral swine known to roam their land, or at a minimum allow someone else to shoot or trap it.
"Whether or not we'll be successful really depends on private landowners," said Keith Kohl of the Oregon Department of Fish and Wildlife. "They are on private land and we can't do it without the landowners' cooperation."
The hairy pigs are native to Europe but have spread to every continent except Antarctica, usually introduced by humans.
The pigs prefer to forage in areas around rivers or streams and can hinder timber growth, tear up irrigated fields, damage white oak stands and erode stream banks. Though mostly vegetarian, they will eat about anything, even small mammals, such as fawns or ewes.
Kohl said feral pigs make it to Oregon in three ways: migration, escapes from exotic-animal ranches and hunters, who set them loose to shoot for sport.
Before the changes in the Legislature, some Oregon ranchers charged money to let people hunt them on their land.
Wendy Brown, executive coordinator of the Washington Invasive Species Council, told The Capital Press there probably isn't a feral swine population in Washington. But the state is concerned about the possible arrival of the pigs from California, Idaho and Oregon.
"The environmental impacts of feral swine are enormous," she told the publication. "The impacts to the agriculture industry are potentially really big as well."
A group of between 50 and 100 feral pigs in southwestern Idaho was culled to 20 through surveillance and tracking in the area, and Oregon hopes to duplicate that success.
Biologists have been warning lawmakers for years that the wild pig populations can expand quickly and with little notice, endangering many Oregon agricultural moneymakers, from timber to wine and alfalfa.
In 2001, the state classified feral pigs as predators and wildlife animals. That made it illegal to let them run loose and legal for people to kill them on their property as a nuisance without a permit.
Before the change, they were considered livestock and couldn't be killed. To hunt the pigs on public land, people must get a state hunting license.
Kohl said other states allowed the pig populations to grow out of control, and now may be past help.
"We're not there yet," he said, "and we'd like to keep it from getting that way."
Copyright 2011 The Associated Press.