A new paper published this week in Nature Scientific Reports quantified the potential for wild pigs – one of the most notoriously destructive and widespread invasive species in the world – to contribute to threatened and endangered species declines throughout the contiguous U.S.
The study offers a much-needed first approximation of the scope of the problem wild pig spread present to imperiled species conservation, offering guidance for allocation of management resources and providing a model for assessing impact risks of wild pigs and other invasive species globally.
The study was conducted by CSP Lead Scientist, Meredith McClure, and colleagues at the U.S. Department of Agriculture and Colorado State University. It identifies over 100 imperiled species that are expected to be vulnerable to predation or habitat destruction where they co-occur with wild pigs, and reveals that most of these species may already share the majority their range extents with wild pigs. Wild pigs are extreme habitat generalists able to survive in a wide variety of habitats. Their highly flexible diets allow them to prey on all groups of terrestrial vertebrates, and their rooting and wallowing behavior has ecosystem-level impacts, destroying habitat for a wide variety of species.
As wild pigs continue to expand their range, both the number of imperiled species impacted and the extent to which each is impacted are only expected to increase. This has important implications for already costly programs to conserve threatened and endangered species and to manage the spread of wild pigs. In 2014, U.S. agencies spent over $1.4 billion on imperiled species recovery efforts, with annual costs of controlling invasive species occupying endangered species’ habitats totaling $29-38 million (1997 $U.S.). U.S. Department of Agriculture annual investments in managing wild pig damage total $20 million. The study highlights taxa and regions where allocation of resources and coordination among imperiled and invasive species management programs may be most effective.