5.10 Invasive and Other Problematic Species and Genes
Invasive species may be one of the most important and widespread issues in conservation biology today because once established, they are expensive to treat, are typically hard to remove, may become permanent components of the community, and have efects that can be irreversible (Reynolds and Souty-Grosset 2012) . Nonnative and invasive species introductions (both plant and animal) continue to pose a threat to native wildlife in North Carolina. Te spread of invasive species has been growing over the last decades, with species of all kinds moving higher in latitude and elevation as changing climate conditions facilitate range expansions. Invasives are particularly threatening to native species with small population sizes and distribution ranges (Vose et al. 2014) . Introductions of nonnative species have occurred in a number of diferent ways, ranging from intended stockings, to range expansions, to acci- dental and deliberate release of animals purchased through the pet trade. Impacts on native species are equally varied—some exotics out-compete native species (e.g., Kudzu and Japanese Stiltgrass), while others cause hybridization (e.g., Red-eared Sliders breed- ing with native Yellow-eared Sliders). Still others can cause direct mortalities to our native resources (e.g., red imported Fire Ants, the Hemlock Wooly Adelgid). Te most important concept to remember is that all of the components within a natural community—whether native, introduced, exotic, or invasive—will have synergistic rela- tionships and cumulative impacts on each other, both positive and negative. Te species discussed in this section do not represent an exhaustive list of all invasive or problematic species; rather, these are examples that represent widespread concerns or species that may be site-specifc. When considering invasive and other problematic species in North Carolina, it becomes clear that a discussion about one topic often leads to the need to discuss several others. Given this complexity of the topic, the information provided in this section has been orga- nized frst by landscapes (aquatic or terrestrial communities), then by category (plants or wildlife). While pathogens may be considered an invasive or problematic species, they are discussed in Section 5.13. 5.10.1 Aquatic Systems—Anticipated Impacts Freshwater systems have a high degree of connectivity that allows invasive species to spread easily and sometimes rapidly from the source to new areas (Reynolds and Souty-Grosset 2012) . Excessive aquatic plant growth can cause many types of impacts but the ones that most often involve local management eforts are habitat degradation, impaired fshing and boating, and blocked hydroelectric turbine intakes (Richardson 2008) . Weed management tac- tics are relatively few and often have limited efcacy, various environmental impacts, and high expense. Management tools include biological, chemical, mechanical, and physical
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2015 NC Wildlife Action Plan
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