5.13 Disease and Pathogens
traumatize gills and inhibit the fsh’s ability to breathe. While most fsh are able to toler- ate a moderate infestation of Gill Lice, if they are sufering from other stressors, such as drought and high water temperatures, fsh kills and population impacts are more likely to occur. Relatively little research has been conducted for these two Gill Lice species. A better understanding of their distribution and life history traits will assist the determination of which fsh populations may be most at risk of experiencing detrimental efects due to infes- tation and mitigating negative consequences of these infections (Vigil et al. 2015) . Tree Flavobacterium species ( F.psychrophilum , F.columnare , and F.psychrophilum ) cause several diseases that result in mortality to freshwater hatchery-reared and wild fshes (Starliper 2011) . Tese particular Flavobacterium pathogens are ubiquitous in temperate fresh- water aquatic environments, within a wide range of water temperatures from just above freezing to 30°C (86°F) and above (Starliper 2011) . F.psychrophilum causes bacterial coldwater disease, which is usually fatal to coldwater fshes such as trout (Starliper 2011) . Chronic infam- mation associated with the disease causes spiral or erratic swimming behaviors and/or spinal column deformities that are similar to symptoms associated with whirling disease. In 2015, whirling disease was detected in the state in Rainbow Trout from the Watauga River. Whirling disease infects young salmonids (i.e., trout, salmon) and is caused by the myxosporean parasite Myxobolus [ Myxosoma ] cerebralis (Snieszko 1975; Sarker et al. 2015). Tis parasite causes physical deformities that cause fsh to swim in circles and is particu- larly fatal for young Rainbow Trout (Sarker et al. 2015) . Te life cycle of the parasite alternates between two hosts: salmonid fshes and an aquatic oligochaete host Sludge Worms ( Tubifex tubifex ). Sludge Worms are a common oligochaete found in stream and lake sediments and are infected by feeding on sediments containing the parasite (Gilbert and Granath 2002; Sarker et al. 2015). Spores developed in the host are released into the water column where they attach and infect fshes. Infected fsh can develop skeletal deformaties, may swim in circles, and ultimately will die as a result of the disease. Spores are released back into sediments when fsh die, thereby repeating the cycle (Ayre et al. 2014; Sarker et al. 2015). Eutrophic impoundments and organically enriched streams are thought to contribute to the infection cycle (Tompson 2011) because density of T.tubifex populations are greater when organic content in sediments are high (Robbins et al. 1989; DuBey and Caldwell 2003; DuBey 2006) . McGinnis and Kerans (2013) hypoth- esized that areas with higher residential, agricultural, and disturbed areas, higher road densities, and lower riparian cover would contribute sedimentation to trout waters that result in favorable habitat for Sludge Worms. 5.13.7 Pollinators—Anticipated Impacts Introduced pathogens from the commercial bumble bee industry are suspected as poten- tial contributors to signifcant bumble bee declines throughout North America (Cameron et al. 2011; Colla et al. 2006; Otterstatter and Tomson 2008; Murray et al. 2013) . Declines in bumble bee species
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2015 NC Wildlife Action Plan
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