The wild pig (Sus scrofa) is one of the most destructive invasive species in the United States and causes an estimated $1.5 billion in damage annually. However, this estimate only takes into account agricultural and property damage as the environmental damage caused by wild pigs is relatively unknown. Understanding this relationship between wild pigs and the habitats they invade is of great importance, especially as wild pigs are rapidly expanding their range. Changes to riparian ecosystems are especially concerning as these systems provide important ecosystem services such as filtration, nutrient cycling, habitat and food web maintenance, and surface water storage. We are examining water quality on a privately-owned property in Alabama that is densely populated by wild pigs. We hypothesize that pig activity in riparian zones increases sediments and other pollutants in surface waters, affecting bank stability and water quality. Water samples are collected to measure concentrations and loads of sediment (TSS), nitrate and nitrite, base cations, and E. coli and other fecal coliforms. Samples are analyzed via qPCR DNA technology for pig fecal bacteroidetes.
Results/Conclusions
Preliminary results indicate that water quality is being impacted in watersheds. E. coli and other fecal coliform colony counts, Dissolved Organic Carbon, sodium, ammonium, calcium, Total Nitrogen, and specific conductivity were all significantly higher at the treatment sites. Nitrate concentrations were lower than expected and can be attributed to high nitrite levels resulting from low Dissolved Oxygen levels, which in turn likely resulted from pig activity in the watersheds. E. coli concentrations were consistently greater than the EPA’s recommendation of 126 cfu/100 mL for recreational waters. DNA analysis detected the pig fecal gene biomarker in samples from all 13 treatment sites, although concentrations varied by date and site. Our research fills a gap of knowledge on the influence of pig damage in riparian systems and uncovers essential information that can influence management of this invasive species to safeguard water quality in local watersheds.