No success yet with birth control for feral hogs

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Associated Press

Posted on April 21, 2010 at 3:34 AM

LUBBOCK, Texas (AP) — There's a saying that when a feral hog has six piglets, only eight are expected to survive.

That's no joke in Texas, however, where the 400-pound beasts do an estimated $50 million in damage to crops and property each year. Texas has half the nation's feral hogs, but they're now found in about 38 other states, up from fewer than 20 states 15 years ago.

One Texas researcher had hoped to slow their rapid reproduction with a birth control pill, but that hasn't worked out well.

Two compounds proved ineffective. One required a very exact dose to work, and the other wore off too soon, said Duane Kraemer, a Texas A&M University veterinarian and researcher.

There also are the problems of getting the hogs to take the drug, keeping it from other animals and ensuring humans who eat hog meat aren't harmed.

"You always wish you could solve the problem quickly," said Kraemer, who has been working on hog birth control options for about 18 months. "I know it's not a simple problem or else someone would have done it already."

The problem keeps getting worse in the nation's second-largest agricultural state. Descended from domesticated pigs who escaped, the hairy-backed hogs are found in nearly all of Texas' 254 counties. They can produce three litters in two years, the piglets can reproduce six months after birth, and the animals have no natural predators.

Hunters in Texas can kill wild hogs any time, but their population is so huge and they reproduce so quickly, the problem can't be solved with a rifle.

"We killed one, but the next day 15 came to the funeral," joked Zachary Yanta, an exasperated farmer who takes his dogs into the fields at night to try to kill the beasts on his property in Runge, 60 miles southeast of San Antonio.

Armed with razor-sharp tusks, the hogs shred fields and pastures and wreck ecosystems by wallowing in riverbeds and streams. Even perennials planted at graves aren't safe.

Kraemer's work is on hold after two federal agencies rejected his applications for grants to keep going.

"They are concerned, but they don't think we can deliver it," he said.

Even if he found an effective drug, there remains the problem of how to get sows to take it, while keeping it away from deer and other animals. A group of A&M students is working on this, and Kraemer expects a report from them at the end of the semester.

Michael Bodenchuk, state director of Texas Wildlife Services, said one option might be injecting the drug into a walnut.

"The hog is the only one with jaws strong enough to crack it," he said.

Bodenchuk said he would like to see a contraceptive used to help reduce the wild hog population. But officials also would need to ensure leftover doses or residue in animal waste didn't cause long-term environmental damage by getting into the soil or water.

There's also the question of what happens to someone who eats a hog with oral contraceptives in her system. Unappealing as the hogs look as they crash through brush, some high-end grocery chains sell "wild boar" for up to $18 a pound.

While researchers scramble for solutions, the hog population is expected to grow even more rapidly as Texas has emerged from a nearly two-year drought that likely kept the population down. With more moisture will come more vegetation and underbrush where piglets can hide and breed.

"They will bounce back quickly with the rains we've been having and will probably do extremely well this year," said Kirby Brown, executive vice president of the Texas Wildlife Association.

Yanta is looking at losing more crops: The hogs' sense of smell is so keen they can go down a row of corn and with precision pick out each kernel planted. But there are other costs as well. Equipment gets damaged when it rolls over holes, at times 1.5 feet deep and 4 feet wide, from the hogs' rooting.

"It looks really like a mine field," Yanta said. "It costs a lot to go ahead to repair the soil afterward."

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