US battling threat of wild pigs

In China, the rush to stop the African swine flu is at fever pitch. In the United States, another battle is raging－against feral pigs.

US authorities are working to reduce the population of wild pig－snow in the millions－because they are considered the most destructive invasive species in the country.

In June 2019, the US Department of Agriculture announced to offer $75 million in funding for the eradication and control of feral pigs.

"Wild pigs will eat just about anything. About 90 percent of their diet is composed of plant matter, while 10 percent is composed of animal matter," said Bronson Strickland, professor of wildlife management at Mississippi State University Service.

"Wild pigs readily consume invertebrates, freshwater mussels, reptiles, amphibians, eggs from ground-nesting animals, small mammals. As for plant matter, unfortunately, wild pigs commonly consume agricultural crops like corn, peanuts, soybean, rice, sorghum."

"Our ecosystem didn't evolve with the presence of these pigs," said Russell Stevens, strategic consultation manager and wildlife and range consultant for the Noble Research Institute in Ardmore, Oklahoma. "That's why their presence is so detrimental to our native plants."

The first feral pigs were brought to the Americas by Spanish explorers in the 16th century. The Spanish released the pigs as they traveled and then hunted them for food if they returned to the area.

Then Eurasian boars were bought to the US, mainly from Canada, in the 1980s and 1990s. At first, they were imported as livestock. They mated with the feral hogs creating today's enormous feral population. Feral pigs are prolific breeders. Each female pig can give birth to six or more piglets a year.

Lafayette, California, about 30 kilometers east of San Francisco, was forced to close nature trails and parks after 40 feral hogs invaded a park at dawn this month, digging up the ground looking for worms and grubs. They caused $50,000 in damage and became aggressive toward dogs and humans.

In November, a pack killed 59-year-old Christine Rollins outside an elderly Texas couple's home where she worked as a caregiver. It was only the fifth death attributed to feral pigs since the 1800s.

Mike Bodenchuk, state director for Texas Wildlife Services, said that unprovoked attacks by wild pigs on people are "very rare".

Around 6 million pigs live wild in parts of North America, mainly in the US South. Three million inhabit Texas alone. They have existed in 17 states for centuries, but recently expanded into 38 states.

The hairy black and brown pigs can weigh as much as 800 pounds, and it is estimated that they cause more than $1.5 billion in damage a year. That includes the after-effects of the pigs' collisions with vehicles.

Wild pigs are also extremely adaptable and can survive in extremely cold climates. Bodenchuk said that in Texas the wild pig population is kept under control by shooting them. Some hunters choose to shoot them from helicopters with semiautomatic weapons.

Jim Cathey, associate director for the Texas A&M Natural Resources Institute, said: "If you have pigs in a trap, they're a formidable animal. They will do a few things. They may pop their jaws so you can hear their jaws clamp together, so that's an auditory warning and if you press them－say, you're trying to get them to go into a trailer or whatever－they'll charge.

"If you pressure them or they are cornered, they will either go around you or through you. They are super powerful; their canine teeth extend beyond their jaw."