The feral pig problem in the United States is about to get worse

Feral pigs have roamed the woods of the United States for centuries and are a major feature of the American countryside, with one Twitter user going viral in 2020 complaining about the “30 to 50 feral pigs” who kept bothering their children who were playing in the yard.

It seems that these traditional boars have now interbred with domestic pigs, creating huge hybrid pigs that are descending en masse from Canada to the United States, ready to cause even greater destruction than usual.

THE Guardian reported in February that these so-called “super pigs” that roam southern Canada are “incredibly smart, very elusive”, larger than their cousins ​​and able to dig tunnels in the snow to survive in harsh conditions. colder climates.

The United States Department of Agriculture (USDA) states that the United States, which brought feral pigs when it settled the country in the 1500s, has about 6 million feral pigs in at least 31 states. These boars, having lived away from humans for many generations, are now considered an invasive species. They usually weigh between 75 and 250 pounds, but can get even bigger.

“Wild pigs are a very successful species due to their generalist diet and habitat preferences, tolerance to a wide range of climatic conditions, and relatively high population growth rate,” Jim said. Hone, Emeritus Professor of Wildlife Ecology and Management at the University of Canberra in Australia, said Newsweek.

Wild boars cause damage to farmland, crops, property and livestock, digging in fields in search of food and attacking other animals and their nests.

“The damage caused by feral pigs is much the same everywhere in the world it occurs – damage to crops, predation of livestock (lambs), damage to water holes and fences, and possible spread of disease” , Hone said. “Environmental damage includes predation of turtle eggs, damage to endangered plant species. Hawaii has had some success fencing feral pigs from the Big Island National Park.”

Feral pigs cause extensive damage to US agriculture (estimated at at least $2.5 billion per year) and also have a widespread impact on biodiversity across the country.

“As a non-native invasive species, they outcompete and prey on native wildlife, including threatened and endangered plants and animals,” said Joshua A. Gaskamp, ​​consultancy lead on wildlife and range at the Noble Research Institute. Newsweek. “Collisions with vehicles are on the rise. And feral pigs carry at least 70 zoonotic diseases that can be transmitted to livestock, humans or other animals. As feral pig populations spread and densities increase across the country, this damage will become more widespread.”

Diseases include leptospirosis, toxoplasmosis, brucellosis, swine flu, salmonella, hepatitis and pathogens E.coliaccording National geographic.

So if these wild boars mate with domestic pigs, what kind of impact could that have on the United States? It depends on the types of traits they end up inheriting, including the reproductive rate.

“The European wild boar and the different breeds of domestic pigs that live in the United States and Canada are all the same species,” Gaskamp said. “Therefore, domesticated and wild-type European boars can and do breed successfully.”

“The difference between a wild type (or an animal genetically closer to a European wild boar) and a domestic pig is the fact that certain traits are more prevalent in various breeds of domestic pig after generations of selective breeding to create an animal desirable for market or show,” Gaskamp said.

Usually, pig farmers selected traits that would benefit them financially, such as high reproductive potential and fast growth rate. This only becomes a problem once these highly productive pigs are free in the wild.

European boars generally have one breeding season per year and produce an average of between three and six pigs per litter. Domestic pigs regularly produce more than eight piglets per litter and do so twice in a single year.

“The reproduction rate of hybrid feral pigs (domestic ferals crossed with boars) is around 6 pigs per litter and 1.5 litters per year per sow on average,” Gaskamp said.

“Domestic pigs or domestic crosses were not designed to survive in the wild, although they do quite well. European boars were selected by mother nature, so they are designed to survive. It is possible that pigs with more domestic gene expression will be slightly larger, but again, this is not a trait that will keep a pig alive in the wild.”

The Guardian reported that early crosses in the 1980s were much larger, but also reproduced faster than expected. This may hold true for newer hybrids.

“During the period of hybridization, we are always faced with a transfer of traits from one population to another, as wild boars become more prolific, perhaps even less fearful of humans and certainly larger,” Domenico said. Fulgione, professor of population ecology at University of Naples Federico II in Italy, says Newsweek.

Hybridization may not be the only major driver for the spread of wild pigs, as another is actually humans moving them across the country so we can hunt them for sport.

“The primary modality that causes feral pig populations to spread is human transport and release,” Gaskamp said. “Wild pigs are fun to hunt, but it’s an incentive to have them near you, and further promotes their existence and spread, even where they are unwanted and in non-native territory. Currently, you You can pay the wildlife department in some states for a tag to hunt an invading feral pig, while in other states you must call the authorities or shoot on sight. Still others allow the trapping and sale of pigs. wild for meat consumption, yet another incentive to keep them.

As populations increase in the near future, either due to hybrid pigs or other reasons, the US food web may end up changing.

“All animal species live in a kind of dynamic equilibrium, the disturbance of this equilibrium affects other species,” said Fulgione.

“In Europe, for example, due to a huge increase in wild boars, we have seen a significant increase in its predators, wolves, but also an increase in some scavengers such as jackals. Even predators, if they are in large numbers, are difficult to manage and make compatible with agriculture and animal husbandry.”

Managing feral pig populations and limiting the damage they cause to America’s economy and ecosystems requires careful planning and effective management.

“Wildlife management should be a shared policy. We can’t continue with different policies from state to state, animals don’t know national borders,” Fulgione said.

Therefore, pigs and their movements should be properly studied before implementing a control strategy that covers all affected states.

“To curb this invasion, communities, states and the national government must have a consistent pest species message and a consistent management plan,” Gaskamp said. “In addition to a cohesive plan or strategy over a wide geographic area, landowners can work together to keep feral pigs off their farms. We can have bigger and longer lasting impacts if we work together on larger geographical areas.

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