Originally published Friday, January 12, 2018 at 06:00a.m.

LAKE HAVASU CITY – Last year, feral swine at Lake Havasu National Wildlife Refuge found out what happens when pork fails a USDA inspection. U.S. Department of Agriculture agents will return to the Refuge this month, and the region’s feral hogs are scheduled to receive another poor grade.

For the second time in a year, USDA sharpshooters will attempt to exterminate feral swine at the refuge.

According to Lake Havasu National Wildlife Refuge Manager Rich Meyers, the USDA is returning in mid-February for a second round of feral pig exterminations, a process that could take years before the region’s feral swine are eradicated completely.

The USDA began its Feral Swine Eradication Plan last February, in coordination with the U.S. Fish and Wildlife Service, with an operation scheduled to last two weeks. The $25,000 operation consisted of a helicopter with crew and aerial sharpshooters, with USFW officials monitoring feral swine from the ground. After less than four days, the effort was declared a success by federal officials, with about 70 confirmed kills. According to Meyers, however, the surviving hogs may have repopulated within the past 12 months.

“Typically, hogs increase their reproduction while under stress,” Meyers said. “We’re seeing more hogs, and it’s possible that they’ve replenished their numbers.”

According to Meyers, a feral sow can give birth to two litters per year, and the exact number of swine at the Refuge can be difficult to count due to their preference toward areas of dense vegetation. According to USFW statements, feral swine are an invasive species throughout the country, the descendants of domesticated pigs that were released or escaped from captivity. Feral swine can cause extensive damage to riparian habitats while searching for food, and are known carriers of leptospirosis, salmonella and E-coli, presenting a threat to human health when they enter gardens and agricultural land.

“Everywhere they are on the refuge, they’re extremely damaging to the habitat,” Meyers said. “We won’t get them all, but we can take out a lot of the sows and keep pressure on them. After a few years, we’ll systematically eradicate them from the refuge.”

Feral swine populations throughout the U.S. exceed 5 million, according to a 2015 Wildlife Society study, and economic losses resulting from damage caused by feral swine is more than $1.5 billion per year.

According to Meyers, this year’s culling efforts will take place throughout the Refuge, although the majority of culling will take place in Topock Marsh, where officials believe the largest population of feral swine may be found. Areas of the refuge populated by feral pigs are almost entirely inaccessible by land, Meyers said, making ground-based hunting impractical for the extermination process.

Federal agencies plan to create a temporary, two-week no-fly zone over the refuge during this year’s extermination, which could begin in the middle of February, Meyers said.