FLORENCE, Ala. - It has all the makings of a horror movie - a 300-pound beast with oversized teeth running amok in forests and fields, eating everything it can.
Instead, it is a real-life scenario that is becoming more common in the Tennessee Valley and across the nation as the feral hog population expands.
Feral hogs, descendants of farm animals that escaped or purposely were set free, are wreaking havoc on farm crops and pastures and destroying wildlife habitat. Wildlife officials estimate the nation's feral hog population at more than 4 million, and estimates are they cause more than $1.5 billion in damage each year.
In Southeast Tennessee, feral hog populations are at problem levels in Polk and McMinn counties and throughout the Cherokee and Smoky Mountains national forests, according to Tennessee Wildlife Resources Agency spokesman Dan Hicks in Crossville.
Hog problems exist in all the counties that border the national forests in Tennessee, Hicks said.
Hunting and trapping are the two most popular methods used to slow the feral hog population explosion. Biologists admit hunters cannot eradicate the population, but say hunting helps keep the animals under control.
In Tennessee, lawmakers have removed game animal status for wild hogs, reclassifying them as a nuisance and liberalizing harvest limits.
"Feral hogs are a huge problem," said Allison Cochran, biologist at Bankhead National Forest. She called them "the number one enemy for native wildlife and plants."
Chris Jaworowski, a wildlife biologist for the Alabama Department of Conservation and Natural Resources, said there are few things wild hogs won't eat.
"A hog is an opportunistic omnivore," he said. "Pretty much anything they can get in their mouth, they are going to eat."
Feral hogs will eat wild turkey eggs and those of other ground-nesting birds, Cochran said. They also eat birds, frogs, deer fawns and other animals they are able to catch.
In addition, feral swine can destroy endangered plants by rooting and wallowing. Erosion caused when the hogs root up the soil can lead to silt in nearby streams and harm rare fish and other animals, Cochran said.
Jaworowski said feral hogs have spread throughout the state in recent years.
"We now have feral hogs in pretty much every county in the state," he said. "It's not just a problem in Alabama. Since 1982, feral hogs have spread from nine states to 45."
Hicks said domesticated hogs, which either can escape or are intentionally released, take to the wild readily.
"No domesticated animal reverts back to the wild quicker than a hog," he said.
It is illegal to release swine into the wild in Alabama and Tennessee or to transport live feral hogs.
Ron Eakes, a supervising biologist at the Department of Conservation and Natural Resources office in Tanner, said the typical feral sow has two litters of four to 14 piglets each year. He said two pairs of wild hogs and their offspring can produce 16,000 piglets in three years.
"With no predators, it doesn't take long for a population of feral hogs to reach problem levels once they move into an area," he said.
Doug Markham with the Tennessee Wildlife Resources Agency said the state's wild hog population has risen dramatically in recent years, prompting lawmakers to declare open season on them.
"We no longer refer to harvesting wild hogs as hunting," Markham said. "We are calling it eradication. We know we will never be able to eradicate them, but hopefully we can slow them down."
Staff writer Ben Benton contributed to this story.