Chapter 3 North Carolina Species
vegetation, eliminated insect larvae (macrobenthics) and other native organisms through predation, and contributed to problems with turbidity in otherwise clear water in small streams (Davidson et al. 2010) . Although eradication or control of invasive species can be economically more expensive than the cost of prevention, measures or programs that address invasive species proactively are usually underfunded (Leung et al. 2002; Allendorf and Lunquist 2003; Ricciardi et al. 2011; Withrow et al. 2015) . Problems and uncertainty with taxonomy for numerous species need to be addressed to understand abundance and distribution better and to develop conservation measures for native species. Research related to these threats and their impacts on certain species was ranked as a high priority. In their book on freshwater biodiversity management, Reynolds and Souty-Grosset (2012) identify fungal crayfish plague ( Aphanomyces astaci ) as another reason for concern with nonnative crayfish. This pathogen is listed by the IUCN as one of the world’s 100 worst invaders (Lowe et al. 2000; Souty-Grosset 2012) because once a watershed is infected, control of its spread is almost impossible. While the disease has not been detected in the United States at this time, indirect evidence from laboratory studies indicates Red Swamp Crawfish can harbor the fungus and act as a vector for translocation of the pathogen (Evans and Edgerton 2002) . There have been no investigations conducted in the United States about the fungus’ mortality impacts to native species. Porcelain disease, or thelohaniasis , has been documented in the Broad, Catawba, French Broad, Hiwassee, Savannah, Yadkin-Pee Dee, Lumber, and Neuse River basins. In crayfish with thelohaniasis , the muscle tissue is progressively invaded leading to deterioration of muscle function and death. Thelohaniasis has been attributed as a cause of epidemics among crayfish in Europe. Generally, the prevalence is less than 5% but there have been occasional reports of prevalence up to 30% (Evans and Edgerton 2002) . The ecological benefits of dam removal are well documented in research literature, and discussion about negative effects often focuses on downstream transport of sediments, nutrients, and toxic materials and upstream movement of introduced fish (Lieb et al. 2011) . Dams may protect imperiled crayfishes by preventing the upstream spread of nonnative or invasive crayfishes, and regulatory agencies that manage dam removals need to consider this potential when considering dam removal projects (Lieb et al. 2011) . Thermal conditions in a watershed may also limit the spread of invasive species (Lieb et al. 2011) . However, factors that can increase water temperatures (e.g., urbanization, climate change, increasing groundwater temperatures) can facilitate movement of invasive species into waters not previously occupied (Eggleston et al. 1999; Mohseni et al. 1999; Steffy and Kilham 2006; Kaushal et al. 2010; Lieb et al. 2011) .
2025 NC Wildlife Action Plan
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