Sept. 19, 2007

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OVERTON – Might it be raining feral hogs this fall? "Raining" might be something of an over-statement, but the wet year could mean bigger litter sizes and more far-ranging herds, said Texas Cooperative Extension experts.

We can be sure that more water and increased food supplies for feral hogs will mean an increase in litter sizes, said Dr. Billy Higginbotham, Extension fisheries and wildlife specialist.

By conservative estimates, Texas has 1.5 to 2million feral hogs. They root up crop land, pastures and landscapes, and compete with more desirable wildlife such as white-tailed deer for food. Though many farmers consider them a nuisance, feral hogs are also a highly sought after game species by hunters. The animals are descended from domestic hogs, Higginbotham said.

"Therefore, it is reasonable to assume that an increase in available nutrition for feral hogs will have a similar effect as it does with domestic swine," he said.

Domestic hogs will produce larger litters when food supplies increase, said Dr. Jodi Sterle, Extension swine specialist.

"Pigs actually respond very quickly to increase feed resources," Sterle said. "(Depending upon conditions) they might have one to one-and-half more pigs per litter."

For example, in the case of domestic swine, a particular breed may have an average litter size of eight. But with food resources that litter size might increase to nine or nine and a half.

"That half is an average. Obviously, you can't have a half pig," she said.

"In domestic pigs, if you increase their energy (nutrition reserves) just prior to mating – we call that 'flushing' – they will actually ovulate more eggs," she said. "It's especially effective if they are in a lower plane of nutrition before."

Feral hogs typically have litters of four to six pigs, Higginbotham said. Just as domestic swine do, they have a 114-day gestation period and can produce two litters a year.

"And it's possible for a female born in the spring to reach sexual maturity six to eight months later, and produce a litter before her first birthday," he said.

"Most of our feral stock in Texas are descended from domestic hogs so what applies to one should apply to the other," he said. "With a drought in 2005 through 2006, then they definitely had a reduced nutrition going into the wet spring of 2007. Feral hogs can produce litters year around, but there are peaks in farrowing in the spring and the fall."

Also, landowners should expect to see feral hogs ranging wider than they have in last couple of years, he said. Feral hogs tend to stay near water sources and where there is vegetation providing heavy cover. During the drought this meant near river bottoms and large impoundments. This year, with even small ponds filled and puddles everywhere, Higginbotham expects they have expanded their range.

The most effective way to control feral hogs is by trapping them, Higginbotham said. But two factors may make conventional methods less effective this year.

One is the expected increase in the number of juvenile hogs. The smaller hogs can worm their way through the metal mesh of many traps. Higginbotham recommended that traps be made with mesh no larger than 4-inch by 4-inch squares.

"The smaller mesh will retain all the hogs trapped," he said. "Control of juveniles is essential if the landowner's goal is to reduce the hog population."

The other factor is that a good to excellent acorn crop is expected this year, he said. Traps are usually baited with shelled corn, but hogs prefer acorns over corn and may ignore the traps once the acorns begin to fall. One solution may be to substitute soured corn (fermented corn) in place of shelled corn.

See the Extension Web site, "Coping with Feral Hogs," at http://feralhogs.tamu.edu/ for more information on trapping, baits and other means of control.

But there's good news too. Along with the probable increase in feral hog numbers, the flush of vegetation from the wet spring and summer should favor other wildlife species, including white-tailed deer, Higginbotham said.