3.4 Crayfshes
• Pollution
• Invasive and other problematic species
• Residential and commercial development
• Natural system modifcations
• Climate change and severe weather
• Transportation and service corridors
• Biological resource use
In their book on freshwater biodiversity management, Reynolds and Souty-Grosset (2012) identify fungal crayfsh plague ( Aphanomyces astaci ) as another reason for concern with nonnative crayfsh. Tis pathogen is listed by the IUCN as one of the world’s 100 worst invaders (Lowe et al. 2000; Reynolds and 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 Crawfsh can harbor the fungus and act as a vector for translocation of the pathogen (Evans and Edgerton 2002) . Tere have been no investigations conducted in the United States about the fungus’s mortality impacts to native species. Te ecological benefts of dam removal are well documented in research literature, and discussion about negative efects often focuses on downstream transport of sediments, nutrients, and toxic materials and upstream movement of introduced fsh (Lieb et al. 2011) . Dams may protect imperiled crayfshes by preventing the upstream spread of nonnative or invasive crayfshes, and regulatory agencies that manage dam removals need to consider this potential when considering dam removal projects (Lieb et al. 2011) . Termal 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; Stefy and Kilham 2006; Kaushal et al. 2010; Lieb et al. 2011) . 3.4.7 Additional Information Te AFS Endangered Species Committee, Subcommittee on Crayfshes published a reas- sessment of the conservation status of crayfshes in the United States and Canada (Taylor et al. 2007 ) that is available online from the US Geological Survey’s Southeast Ecological Science
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2015 NC Wildlife Action Plan
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