Non-Native, Invasive Species
The environmental harm caused by non-native, invasive species (such as wild hogs, nutria, Burmese pythons, northern snakeheads, etc.) was created by man. Human action led to these animals being released in the United States. Wild hogs do not belong in North America. They harmfully impact agriculture, native vegetation, vertebrate and invertebrate fauna, soil properties and water quality causing an annual negative economic impact of $2.5 billion dollars in the United States.
Wild Hog Damage in Georgia
Agriculture, Timber and Native Vegetation Damage
A six-page wild pig questionnaire was administered to farmers and landowners by the University of Georgia – Warnell School of Forestry and Natural Resources in January of 2012. A total of 1200 surveys were delivered to randomly selected recipients and 471 useable surveys were returned yielding a 39.25% response rate.
The below damage estimates, figures and graphs were provided by the 2012 Georgia Wild Pig Survey Final Report. Respondents reported an average of $12,646 dollars in crop damage per person or an average loss of $30 per acre attributed to wild pigs. This average produced an estimated 57 million dollars ($57,005,321) from wild pig damage to crops and/or crop related damage in Southwest Georgia. Respondents reported an average loss to items other than crops (e.g., timber, food plots, lease values, etc.) due to wild pigs during 2011 of $5,381 per person yielding a loss of $12.75 per acre. This average produced an estimated $24 million dollars ($24,256,336). Together losses due to wild hogs reportedly exceeded 81 million dollars in 2011. Damage estimates in this mail survey referred only to the 41 counties located in the Southwest Cooperative Extension District.
Eighty-seven percent of respondents agreed or strongly agreed that feral hogs are a nuisance. Ninety percent of respondents did not enjoy seeing feral hogs on their property and 81% worried about problems feral hogs may cause to their property. Eighty-two percent agreed or strongly agreed that feral hogs should be eliminated wherever possible.
Native Wildlife Affected
Reptiles and amphibians such as lizards, salamanders, frogs, snakes and turtles are vulnerable to predation. A research study (Jolley et al. 2007) at Fort Benning, Georgia observed a single boar consume 49 spade-foot toads during one feeding cycle. Using area estimates and consumption rates, the researcher estimated an entire population of feral hogs could consume 2.85 million reptiles and amphibians per year within Fort Benning’s 736 km² area. Wild hogs consume eggs of ground-nesting birds like turkey, quail, ducks, geese and shorebirds. They also destroy reptile nests of alligators as well as threatened and endangered species such as loggerhead sea turtles.
Soil Erosion and Degraded Water Quality
Wild hog wallowing and rooting increases soil erosion and degrades water quality. Silt deposits and water contamination along streams and coastal areas contribute to declines in aquatic plants, freshwater mussels and insects. During dry seasons, wallowing also creates competition with native wildlife for limited water resources. Wild hogs elevate waterborne bacteria levels by depositing their urine and fecal matter in rivers and creeks. This severely damages downstream water quality with bacterial contamination which can risk human health. Especially if the contaminated water is used to irrigate fruits or vegetables marketed for human consumption.
Disturbed soil in agricultural fields from wallowing and rooting causes significant damage to plant roots, soil integrity and soil nutrients. The result is widespread soil erosion which damages planting, harvesting and irrigation equipment along with extensive vegetation loss which reduces agricultural crop yields. The trampled, low-quality soil which remains is often potholed and inhabited by invasive plants requiring extensive labor to repair before another crop rotation can be introduced. Every wild hog related event produces a financial expense to producers and landowners which negatively affects their annual income.
Wild Hog Diseases, Viruses and Parasites
Wild hogs are known to carry bacterial diseases such as Brucellosis, Leptospirosis, E. coli, Salmonellosis, Tuberculosis and Tularemia; viral diseases such as African Swine Fever (ASF), Classical Swine Fever (CSF or Hog Cholera), Foot and Mouth Disease (FMD), Hepatitis E Virus (HEV), Influenza A Viruses (H1N1 and H3N2), Porcine Circovirus type 2 (PCV2), Porcine Epidemic Diarrhea (PED), Porcine Reproductive and Respiratory Syndrome (PRRS), Pseudorabies Virus (PRV), Vesicular Stomatitis Virus (VSV) and at least 45 different parasites (external and internal) which pose a parasitic disease threat such as Toxoplasmosis and Trichinosis to livestock, wildlife, pets and humans.
Disease transmission from feral pigs to domestic livestock is a major concern to the farming industry. Some of these diseases are swine specific (both feral and domestic) but others affect cats, dogs, sheep, goats, cattle, horses and native wildlife. Infectious diseases that are significant to livestock include African Swine Fever (ASF), Classical Swine Fever (Hog Cholera), Bovine Tuberculosis (TB), Foot & Mouth Disease (FMD), Pseudorabies Virus (PRV) and Swine Brucellosis. Zoonotic diseases transmissible from wild hogs to humans include Brucellosis, Cryptosporidiosis, E. coli, Giardiasis, Leptospirosis, Rabies, Salmonellosis, Swine Influenza Viruses, Toxoplasmosis and Trichinosis.
The seven-page brochure “Diseases of Feral Swine” written by the University of Georgia – College of Veterinary Medicine is the most thorough and informative document concerning this topic.