The Economist explains

Why are feral pigs so hard to control?

By E.H.

ON MAY 23rd the United States Department of Agriculture will meet to discuss the pressing topic of feral pigs. Whether wallowing in cool water or ruining a farmer's crops, these beasts, which number 6m or so, are an increasing nuisance. At their worst, they can damage crops, spread diseases, attack humans and kill livestock. One was recently responsible for causing an accident on a new 85mph toll-road. And things are getting worse: a study from Texas A&M University estimates that they are likely to triple in number over the next five years. Why is it so hard to control feral pigs?

Introduced to America in the 16th century, and related to the wild boar found in Europe, feral pigs can be found in 75% of all states. No single law exists to control them and regulation differs between states: whereas in Missouri they can only be shot if stumbled upon, in Texas (the state with the highest feral-pig population) hunting is actively encouraged. A "pork chopper" law allows Texan hunters to shoot feral pigs from helicopters, and some individuals in Louisiana have even built their own pig-hunting drone. As well as being popular with hunters, feral pigs are cheaper for game-rearers to breed than deer. (They are also tasty to eat.) In Michigan and Pennsylvania proposed bans to stop the private breeding of pigs for hunting have caused quarrels between game-ranch owners and wildlife officials.

Feral pigs' dual nature—considered pests by farmers, but valued by hunters—makes it hard to pass laws to control them. Two other factors also contribute. Nearly 70% of land in America is privately owned; in Texas the figure is 95%. Hogs do not care, and will happily wreak havoc wherever they can, whether on public and private land. But it is difficult for legislators to impose breeding and hunting laws on private landowners. Secondly, it is hard to nail down the definition of a feral pig. State-issued definitions may assume that they have the characteristics of wild boar, even though many feral pigs look more like their domesticated cousins. Several pig rearers in Michigan have questioned the breeding ban on the basis that domesticated pigs should be defined as those reared in captivity, whatever they happen to look like. The problem is that they sometimes escape.

In some states, legislation is being introduced to redefine the term "wild animal" to exclude feral pigs in captivity. This is good news for those rearing pigs for hunting, but less welcome to those who consider them pests whose number should be limited. Meanwhile, discussions continue over how best to address this beastly problem.

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