Chapter 5 Threats
5.4.1 Agriculture - Anticipated Impacts As with all threat categories, there can be positive or negative impacts to wildlife depending on its scale and location. Potential impacts (both positive and negative) to fish and wildlife resources from agriculture are numerous. Impacts that can be harmful to wildlife include loss of habitat from conversion of forested or early successional land to cleared agricultural land, erosion of agricultural fields that leads to increased turbidity and sedimentation in surface waters, and contamination from application of pesticides and herbicides. Agricultural crops can provide an important food resource for many wildlife species; however, depredation impacts from wildlife can be significant on agricultural commodity crops. On the positive side, harvested crops within the Coastal Plain provide suitable fall and winter food supplies for waterfowl, Black Bear, White-tailed Deer, and other small wildlife species. Clearing forested or early successional land and converting it to agriculture can displace birds and small mammals that rely on this community type and reduce the number and diversity of species inhabiting the area. The loss of forested habitats that serve as corridors for species moving among adjacent habitats can be especially harmful to wildlife as it reduces available cover for predator avoidance. Agricultural practices also affect wetlands, streams, and groundwater in several ways. Wetlands and other similar habitats can be converted directly to agricultural land or their functions can be lost by changes to the soils or hydrology from practices, such as ditching and draining. Furthermore, surface and groundwater hydrology can be affected by irrigation. Without appropriate sedimentation and erosion control measures, rain events can lead to erosion of cleared fields resulting in increased turbidity and sedimentation of nearby surface waters. Increased turbidity and sedimentation affect foraging and reproduction in streams and lakes and can lead to changes in community composition and species extirpation. In the Coastal Plain, pumping of water during high-water events can result in sedimentation, contaminants, and large volumes of freshwater being dumped into our estuaries, which can negatively affect marine species. Agricultural land uses that include aerial spraying of pesticides and herbicides can affect local amphibian populations when wind carries chemicals into nearby surface waters and wetlands. Little has been published about this source of contamination, but research conducted in California found a significant relationship between amphibian declines in locations with known populations and pesticide drift from upwind sources of agrochemical applications (Davidson 2000) . Studies have shown that greater cattle access to wetlands contributes to a higher prevalence of Frog Virus 3 (FV3) (Gray et al. 2007a) . Pathogenic relationships between cattle and amphibians can occur when suitable hosts are present in drinking water supplies. For example, American Bullfrogs are suitable hosts of the human pathogen Escherichia coli (E. coli), which can provide an exposure pathway between food safety and human consumption when cattle operations
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2025 NC Wildlife Action Plan
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