Some very intelligent feral pigs are having their way with crops, gardens and wildlife, and people can’t figure out how to stop them.
The Wildlife Society, which supports killing wild pigs because of their effects on wildlife and ecosystems, summarizes the damage they can cause:
Feral swine are one of the greatest vertebrate modifiers of natural plant communities. Feral swine damage to property, agriculture, and natural resources often occurs as a result of their aggressive rooting (i.e., grubbing, plowing, digging) activities at and below the surface of the soil. In sandy soils, feral swine may root to a depth of 1 [meter] but even shallow rooting can cause significant soil erosion. Wallowing activities may reduce water quality and disrupt sensitive wetland ecosystems. Other documented damage includes destruction of livestock fencing, damage to farm equipment in rooted areas, and predation on young livestock, ground nesting birds, amphibians, reptiles, and other wildlife. Economic losses resulting from feral swine damage is estimated at greater than $1 billion per year and is increasing.
Wild pigs may also carry nearly three dozen diseases that they can pass on to humans and other animals. They also threaten efforts to reintroduce native wildlife: for example, the federal government has been trying to increase the populations of sand dune lizards and lesser prairie chickens, both of which the pigs eat.
The pigs are hard to stop in part because they are very intelligent. “They’re much brighter than I am,” said New Mexico veterinarian and Land Commissioner Ray Powell. “If they had the dexterity, they’d be driving vehicles around. I mean these guys are really smart.”
There are more than five million wild pigs in the United States. They have made Texas their own and are working towards dominance in other states as well.
Feral swine often spread from state to state through the intervention of sport hunters who want their prey nearby. As a non-native species, they can wreak havoc on local species and ecosystems.
Officials say that the damage swine cause in New Mexico is more devastating now that the state is heading into a third straight year of drought. The pigs are so smart that they have figured out how to break the floats in stock tanks that hold water for livestock so water will continue to flow into their mud baths, leaving less water for ranchers’ animals.
The federal government has decided to make New Mexico Ground Zero for a joint federal-state crusade against feral pigs. Wildlife Services (WS), an arm of the federal U.S. Department of Agriculture (USDA) that private parties can hire to kill animals, is so serious about this battle that, for the first time, it is teaming up with a state government to eradicate the swine. WS has earmarked $1 million in taxpayer dollars for this endeavor.
The government will deploy and evaluate a number of tactics against the pigs to learn which are most effective in particular circumstances. They will focus on using helicopters to track pigs across large areas. Helicopters are also key to aerial gunning, or shooting the animals from the air. Other popular killing methods are trapping, snaring, shooting and using trained dogs.
Officials have to work fast because wild pigs learn fast. They have figured out how to foil a variety of traps. They hide out during daylight, frustrating their would-be killers who cannot locate them. Officials rely on “Judas pigs” to lead them to families of swine: They trap and shoot an entire family except for one sow, whom they radio collar and follow as she searches for a new family to join. When she finds one, they repeat the process.
Reducing the wild pig population by killing individuals is a losing battle. Estimates indicate that people must kill 70% of a local population just to stay even because pigs produce large litters year-round. That would mean killing 3,500,000 across the country every year just to keep the population from increasing. It is hard to imagine the government pulling off an even larger bloodbath every year in an attempt to reduce the population.
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