Monday, April 26, 2021

Bait kills wild pigs

Scientists at the Louisiana State University AgCenter and the university’s chemistry department are developing a bait and delivery system to help reduce the population of feral pigs. 

Glen Gentry, LSU AgCenter feral hog specialist, and John Pojman, a chemistry professor, have been working for years to create a bait and delivery system that minimizes the risk to off-target animals, the LSU AgCenter reports.

Scientists had to choose a formula that was more attractive to hogs based on features such as smell and texture than other animals such as deer or raccoons.

“It took us two years to determine what we were going to use in our matrix,” Gentry said in the release. “We landed on dehydrated fish. But that’s not before we went through things such as maple syrup or marshmallows.”

They will use sodium nitrite, as the poison. While it is a common food additive in products such as bacon, it is lethal to pigs at fairly low levels.

The challenge with sodium nitrite is that it breaks when it becomes moist; then it gives off a chlorine-like odour that repels pigs.

Their first thought was to encapsulate the sodium nitrite, similar to a gel cap. But Pojman and his doctoral students came up with an alternative idea.

“All we had to do was raise the pH (acidity),” Pojman said in the article. “Using some basic general chemistry and putting some additives to keep the pH high enough, we can make it so it is stable.”

Doctoral students Anthony Mai and Anowar Khan helped develop the bait, which has a round and soft texture. When dropped from a height of approximately four feet, it will bounce nearly a foot, the researchers said. 

The soft texture allows the pigs to swallow it whole, leaving no remains of the bait for any other animals that might come along.

Feral hogs have a unique metabolism, the report said, so sodium nitrite is more effective and poses a low risk to humans. 

Even if the hogs ate a sublethal dose and a hunter were to kill it and eat it later, researchers said there is no danger to them.

 Scavengers could also safely feed on a carcass.