Wild boar are associated with a number of concerns, and there is great interest and necessity in managing or eradicating them in Canada. Wild boar are considered invasive – they are not native to the area, and therefore they disrupt entire ecosystems. Issues are exacerbated by the fact that wild boar can reproduce so quickly, and have very few predators. The issues can be grouped into several categories:
Wild boar feed mainly on plants, and when present in large numbers can affect species abundance and richness, altering vegetation communities. Their rooting and wallowing behavior can lead to soil erosion, and disturbance from wild boar can even change soil properties and nutrient cycles. In sensitive riparian areas, wild boar can degrade water quality and general riparian health through erosion, sedimentation, eutrophication, and altering aquatic vegetation communities. This can of course affect fish habitat as well as countless other life forms. There is particular concern with wild boar consuming nesting bird eggs. They will also feed on small mammals, birds, amphibians, and invertebrates. In a more indirect way, they compete with native wildlife as they occupy a broad niche that removes resources from native wildlife who are specialists.
Wild boar can cause extensive damage to croplands through feeding as well as mechanical damage when they trample and/or defecate on the crops. They will also damage fences, agriculture equipment (from large holes left in fields that equipment runs over), lawns, golf course turf, grain bags and bins. Economic losses in the United States, where there is more research on the matter (and more pigs), is estimated to be nearly $1 billion per year.
There is considerable concern about disease transfer between feral wild boar, livestock, wildlife, and humans. Although there is no evidence of diseases within Canada’s wild boar population, wild boar have the potential to carry a number of diseases, and there is no disease testing or monitoring in wild boar operations. For human health, diseases of concern include Trichinella, Influenza, and Hepatitis E. For livestock there is pseudorabies, Swine Brucellosis and Porcine Reproductive and Respiratory Syndrome Virus among others. Each of these diseases could have enormous impacts on the domestic swine industry. Several diseases are spread by the passing of bodily fluids, and therefore shared feed or contaminated crops could cause illness.
There have been several cases of aggression towards humans and livestock from wild boar. They may prey on small livestock, such as poultry, and have been known to harass cattle and even kill calves. The presence of wild boar can cause great stress to a herd. Several media articles highlight attacks on humans, and although many of these have occurred to people who have cornered them on a hunt, such cases can be fatal.
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