Of Feral Hogs, Feral Cats, and Other Western Invaders

Funny how things converge at odd moments. Three or four weeks back, I was reviewing arrangements for the trip son-in-law Chris Kolakowski and I have been putting together for a Texas feral hog hunt. The TV news story at that moment was about the just-released Western Governors’ Association (WGA) list of the top 50 invasive species in the West.

The Association is headquartered in Denver, and includes the governors of 19 western states and three U.S. territories in the Pacific. This invasive species stuff is a big – and growing – deal; The Nature Conservancy estimates that management of invasive species in the U.S. exceeds $120 billion annually and impacts an area the size of California. The West’s forests, rangeland, water and cropland are under siege by seemingly limitless numbers of invading species. Most all of the states have invasive species councils. To get an overall assessment, the Association surveyed coordinators in each member state and territory. The resulting composite list of the top 50 species (25 aquatic and 25 terrestrial) is intended to help state managers better understand regional risks and improve cross-boundary management strategies.

The aquatic species list starts with 1) Eurasian Watermilfoil, 2) Quagga and Zebra Mussels, then works its way down through 7) Northern Pike, 10) Whirling Disease, 19) Nutria, 21) Grass Carp, and ends at 25) Western Mosquitofish. The terrestrial species at topped by 1) Salt cedar, 2) Cheatgrass, 3) Canada thistle, then down through 6) Feral Hog, 13) Feral (or spay-neuter-release) Cat, 16) Yellow starthistle, and ending at 25) Little fire ant. (The whole list and more information can be found by googling “WGA Top 50 Invasive Species.)

This report provides an interesting look at issues facing the West as a region, but from state to state, and county to county, of course, the rankings will vary greatly.

For example, feral cats are at the middle (#13) of the list of 25 regional invasive terrestrial species, but in Hawaii they are at or near the top of the Hawaii Invasive Species Council’s list. They are identified as major instinctive predators of native birds and insects – even if well-fed. The Council notes that “feral cats on islands have contributed to the extinction of 33 species and are the principle threat to 8% of critically endangered birds, mammals, and reptiles.”

The risks of feral cat damage in the West are a reflection of national trends. The American Bird Conservancy notes that the number of domestic cats in the U.S. has tripled in the last four decades. It has long labeled the “feral and outdoor” portion of that growing population an invasive species, killing well over a billion birds annually – an unsustainable predation level for many already-declining species. (See abcbirds.org/threat/cats-and-other-invasives/.) According to a 2010 University of Nebraska-Lincoln Extension Report, “Feral Cats and Their Management,” the outdoor and “ownerless” cats account for $17 billion in economic loss from annual predation on U.S. birds alone. (Losses related to small mammals, reptiles and amphibians are calculated separately.)

Feral hogs are slightly higher on the WGA list (#9), but their damage to economies is far more obvious to most observers. In Texas, the million and a half wild hogs are near the top of the list. Here alone, the hogs cause an average of $52 million damage annually to the agricultural industry. This damage includes rooting of pastures and rangeland, consumption of native vegetation, negative impacts on water quality, predation on other wildlife, and more.

In California, at least 45 counties report wild boar or feral hog damage, with estimates of up to and beyond 100,000 animals. Costs of agricultural damage range up to a billion dollars annually, with a much higher potential as the critters continue to increase. Oregon estimates wild pig numbers in the 5,000 range, is seeing agricultural economic damage, and has instigated an aggressive effort to eradicate the animals. While Washington has yet to see an established population of feral hogs, the Washington Invasive Species Council considers them a serious threat to the state’s agriculture, livestock, and natural resources, with many billions of dollars at risk. In early January of this year, the Council held a public meeting to share and assess the feral hog threat. (Learn more at www.invasivespecies.wa.gov/feral-swine-information.shtml.)

None of the 50 species identified by the WGA are to be taken lightly. They pose grave threats of one type or another to our livelihoods, our recreation, and our future. We must all do our part as new ways of managing the risks are developed.

In the meantime, if you are reading this the evening it posts, hits the newsstand or your delivery box, know that Chris and I are sitting in the dark somewhere outside Wichita Falls, with the intention of trimming Texas’ feral hog population. Amazing, isn’t it, to have a red flashlight that reaches out to 200 yards? We are doing our best to help. I will be filing a report.