Chapter 5 Threats
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 efforts are habitat degradation, impaired fishing and boating, and blocked hydroelectric turbine intakes (Richardson 2008) . Weed management tactics are relatively few and often have limited efficacy, various environmental impacts, and high expense. Management tools include biological, chemical, mechanical, and physical measures, and often require long-term funding commitments to control sources and new occurrences (Richardson 2008) . A partnership of state and federal agencies has developed the North Carolina Aquatic Nuisance Species Management Plan (NCANSMP), which includes an aquatic nuisance species list and policy recommendations. The list includes invasive, nuisance, and nonnative species currently known from North Carolina and those considered at risk of becoming a nuisance though they are not currently known to be in the state, including species that have commercial or recreational value in North Carolina. Management of invasive aquatic species also needs to include outreach to the public as a means of reducing anthropogenic-related sources (e.g., bait bucket dumps, aquaria and aquaculture releases, hitchhikers on boats and trailers) and involving stakeholders in monitoring and remediation programs. A detailed risk assessment and studies on distribution, ecology, and genetics of known potential invaders can be used to develop prevention and management programs for aquatic invasive species (Reynolds and Souty-Grosset 2012) . Native species introduced into areas where they would not normally be found can create competitive pressures for food and habitat use. Blueback Herring introduced to mountain reservoirs have caused the collapse of Walleye populations that now must be maintained by stocking. The Crayfish Taxa Team identified five crayfish species considered invasive and of concern in North Carolina. In the Mountain ecoregion, the Kentucky River Crayfish has been found in large creeks and small river systems, and the Coosa River Spiny Crayfish has been found in the New and Little Tennessee river basins. In the Piedmont ecoregion, Rusty Crayfish and Virile Crayfish have been found in headwater streams, small and large creeks, small and medium rivers, and reservoirs and impoundments. The Red Swamp Crawfish has the most widespread distribution and is found in all freshwater systems throughout the state. Crayfishes that are spread to habitats outside their natural range can affect the distribution of native species as well as the dynamics and biodiversity of the community (Reynolds and Souty-Grosset 2012) .
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2025 NC Wildlife Action Plan
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