U.S. Department of Agriculture (USDA) officials are moving forward with field trails in Texas and Alabama to help determine the effectiveness of sodium nitrite toxic bait for removing feral hog sounders in natural settings.

USDA’s Animal and Plant Health Inspection Service (APHIS) received an Experimental Use Permit (EUP) from the U.S. Environmental Protection Agency to conduct the sodium nitrite toxic bait field trials.

“Wildlife Services takes the selection and use of toxic baits for use in wildlife damage management very seriously. The final environmental assessment, FONSI (Finding of No Significant Impact) and EUP are the result of years of collaborative research by WS and multiple private, state, federal and international partners,” WS Deputy Administrator Bill Clay said. “With these in place, we can now begin field trials to help determine the effectiveness of the sodium nitrite toxic bait for removing feral swine sounders in natural settings, as well as any potential impacts to non-target wildlife.”

The agency will work with landowners to identify and target three to nine feral hog sounders, which are social groups that contain both mature and juvenile feral hogs.

Bait delivery systems designed to prevent access by non-target wildlife will be filled with placebo bait placed in the sounder territories and monitored with motion-activated cameras. Following a period of acclimation to confirm feral hog use of baited areas, the placebo bait will be replaced with sodium nitrite toxic bate for two nights.

At least 30 feral hogs and no more than 30 raccoons will be live-captured and radio-collared prior to baiting in order to monitor movements and exposure to bait.

Sodium nitrite is a meat preservative commonly used to cure meat, such as sausage and bacon. When consumed in large amounts over a short period of time, it is toxic to feral hogs.

The mode of death is similar to carbon monoxide poisoning. Once enough bait is eaten, the feral hog gets faint, is rendered unconscious and quickly dies. In most cases, feral hogs die within 2.5 to 3 hours after eating a lethal dose.

Feral hogs are a destructive and invasive species that causes damage and disease threats to crops, public property, native ecosystems, livestock health and human health.

More than 6 million feral hogs are located in at least 35 states across the U.S. Their damages to agricultural crops alone are estimated at $190 million each year.

“Although trapping, aerial operations, and recreational hunting of feral swine have effectively reduced damage in some areas, studies show that at least 70 percent of feral swine must be removed each year in order to prevent population growth,” Clay said. “Should the U.S. Environmental Protection Agency approve the toxic bait for use with feral swine, it could become another tool in the toolbox for integrated feral swine damage management.”

The development of tools and techniques for use in feral hogs damage management supports the National Feral Swine Damage Management Program—a nationally-coordinated effort among federal, state, tribal and local entities to manage feral hogs damage and stop their spread.

A factsheet has more information about the sodium nitrite toxic bait for feral hogs.