5.11 Pollution and Contaminants
Iqbal et al. 2009; Knott et al. 2010; Pain et al. 2010; Tomas 2013) . Tomas (2013) suggests that the reluctance of hunters and legislators to support use of nontoxic rife ammunition may be based on perceptions about availability, price, and efectiveness of substitute ammunition (such as steel, copper, or copper-zinc alloy shot). However, it was reported there are as many as 48 diferent hunting rife cartridges manufactured in the United States that contain lead-free ammunition, and they are readily available from national retailers (Tomas 2013) . 5.11.3 Airborne Pollutants—Anticipated Impacts Animals are exposed to air pollutants through breathing, ingestion, or absorption through the skin (in the case of amphibians). Te response of an organism depends on many fac- tors, including the type of pollutant and the magnitude and duration of exposure. Tere are three general pollutant types: gases (e.g., ozone), non-acidic chemicals (e.g., metals, diox- ins), and acidic chemicals (e.g., nitrates and sulfates). Te burning of fossil fuels releases sulfur dioxide and nitrogen oxides, which are transformed in the atmosphere and returned as acid precipitation. Gases generally afect animal respiratory systems. Metals may afect their circulatory, respiratory, gastrointestinal, and central nervous systems, particularly the kidney, liver, and brain. Dioxins bioaccumulate, or build up in the body by concentrating in body fat, and are resistant to biological breakdown. A study of earthworms showed they accumu- lated dioxins up to fve times the concentration found in the soil. While not lethal to the worms, it could afect many bird and small mammal species that rely on them as a food source. Acid rain reduces soil bufering capacity and eventually results in changes to vegetation and acidifcation of streams and surface waters. Many studies have shown that aquatic invertebrates, fsh, and other organisms are greatly afected by low pH conditions, with species composition declining as pH drops. Acid rain impacts on fsh are occurring in many countries, including the United States, but evidence in North Carolina is limited. Acid deposition is a possible cause of declines in amphibian populations, particularly those that use ephemeral waterbodies that are susceptible to precipitation events. Reproduction is most vulnerable because early life stages are more sensitive to changes in water chemistry. Air pollutants also afect wildlife indirectly by causing changes in the ecosystem. Vegetation provides cover for protection from predators and weather, provides breeding and nesting habitat, and also serves as a food source. Terefore, any change in vegetation could indirectly afect animal populations.
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2015 NC Wildlife Action Plan
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