Feral swine, often called wild hogs, are domestic pigs (Sus scrofa) that have escaped or been released into the wild. These animals are considered one of the most destructive invasive species across the United States due to their adaptability and high reproductive rates. While Colorado does not currently possess an established, self-sustaining breeding population, the state maintains a zero-tolerance policy for any transient individuals. Officials treat any sighting as an immediate threat, focusing on rapid removal to safeguard agricultural interests and natural ecosystems. Colorado became the first state to successfully eradicate its feral swine herds, but the threat of re-entry from neighboring states remains a concern.
Current Status and Historical Presence
Feral swine were first documented in Colorado during the 1970s. The problem became more pronounced in the early 2000s, with two significant herds forming on the southeastern plains. One group in the Big Sandy Creek drainage (Cheyenne and Kiowa counties) was estimated to contain approximately 250 animals at its peak. A second population of about 100 hogs was located near the Cimarron River in Baca County.
These populations were located in the eastern part of the state, suggesting movement from neighboring states like Kansas and Oklahoma. Colorado Parks and Wildlife (CPW) and partner agencies initiated a coordinated, long-term removal effort. The eradication campaign proved successful, and Colorado declared all established populations eliminated around 2018. The state continues to monitor for new arrivals, focusing on preventing the establishment of any breeding groups.
Ecological and Agricultural Impacts
The aggressive stance toward feral swine is rooted in the damage these animals inflict on the environment and the economy. Their “rooting” behavior, where they use their snouts to tear up soil in search of food, causes severe land degradation. This activity destroys crops, pastures, and native vegetation, leading to increased soil erosion and reduced water quality. The annual cost of damage from feral swine across the United States is estimated to be in the billions of dollars.
Feral swine compete directly with native wildlife for resources, displacing species like deer and turkey. They are also opportunistic predators that consume the eggs and young of ground-nesting birds, small mammals, and reptiles, disrupting local food webs. Sows can breed at six months of age and potentially produce two litters per year, allowing populations to increase exponentially if left unchecked.
A significant concern is the ability of feral swine to transmit more than 30 different diseases and parasites to livestock, wildlife, and even humans. A notable incident in Colorado involved the spread of Porcine Reproductive and Respiratory Syndrome (PRRS) to a commercial hog production facility. This outbreak resulted in the depopulation of approximately 6,000 domestic pigs to contain the virus. Such disease transmission poses a direct threat to the state’s agricultural industry.
Colorado’s Eradication Strategy
Colorado pursues full eradication rather than population control. The state legally classifies feral swine as “unregulated livestock” rather than a game species. This classification removes the need for traditional hunting regulations, permitting agencies and private landowners to remove the animals immediately upon sight. This streamlined legal framework is a core component of the state’s response.
The eradication effort is managed by a multi-agency task force, which includes CPW, the Colorado Department of Agriculture, and the U.S. Department of Agriculture’s Wildlife Services. Specialized methods were employed to eliminate former herds, such as aerial surveillance and hunting from aircraft for locating sounders in remote areas. The task force also uses sophisticated box and corral traps to capture entire family groups simultaneously, a practice known as “whole-sounder removal.”
Monitoring for new incursions is continuous, utilizing techniques such as environmental DNA (eDNA) sampling in water sources and a network of trail cameras. Citizens are encouraged to report any sightings of feral swine immediately to USDA Wildlife Services or CPW. This proactive approach ensures that transient animals crossing state lines are quickly located and removed, preventing the re-establishment of breeding populations.