5.13 Disease and Pathogens
increase the likelihood of a population being severely impacted by these pathogens. While treatment of individual populations is difcult, protocols are being investigated through various scientifc research programs (Rollins-Smith et al. 2011) . Current measures to prevent extinction and preserve genetic diversity primarily involve captive breeding of healthy ani- mals for reintroduction to areas where the fungus is not present and protection of popula- tions unafected by disease through conservation actions. Batrachochytrium dendrobatidis (Bd) is an infectious fungus that can be introduced to water and soils by infected animals and has been found to afect numerous amphibian spe- cies, especially Anurans, including species found in North Carolina (Parris and Beaudoin 2004) . Tis fungus is known to kill from 50% to 80% of the individuals in infected populations, and surviving animals or other host animals can maintain the infection in the population (Gagliardo et al. 2008; Cheng et al. 2011; Blaustein et al. 2012; McMahon et al. 2012; Phillips and Puschendorf 2013; Louca et al. 2014) . Some amphibian species are protected from infection by their skin mucus excretions, but exposure to pesticides can alter immune defense and lead to susceptibility to parasites and pathogens (Lannoo 2009; Rohr et al. 2008; Rollins-Smith et al. 2011) . Ranaviruses are associated with diseases in wild and cultured fshes, amphibians, and reptiles (Robert et al. 2007; Gray et al. 2007a; Brunner et al. 2015) . Tey are reported to be most lethal to amphibian larvae with mortality rates as high as 90% or more (Harp and Petranka 2006; Gray et al. 2007) . In the United States, there is a high risk of exposure for wild populations to the ranavirus Frog Virus 3 (FV3). Host reservoirs for FV3 include exotic species such as African Clawed Frogs ( Xenopus laevis ), which are commonly raised in captivity for the pet trade and sold across the United States, when they are released into the wild (intentionally or accidentally) (Robert et al. 2007) . Te Regina ranavirus is highly infectious and can be virulent to Caudata (urodela) amphibians such as the common Tiger Salamander, likely because they lack natural antimicrobial peptides associated with the more evolved immunosystems of other amphibian taxa (Froese et al. 2005; Sheafor et al. 2008) . Ranaviruses present at aquaculture facilities can be 2–10 times more lethal than wild strains and can pose a particular risk to frogs in the Ranidae family, thereby contributing to their population declines (Hickling 2011) . 5.13.2 Birds—Anticipated Impacts According to the NWHC, avian vacuolar myelinopathy (AVM) is a recently discovered neu- rological disease afecting waterbirds, primarily Bald Eagles and American Coots, in the southern United States. AVM has also been confrmed as the cause of death in Mallards, Bufeheads, Ring-necked Ducks, Canada Geese, Killdeer, and a Great Horned Owl. Birds afected with AVM lack muscle coordination and therefore have difculty fying and swim- ming. Te cause of the disease is unknown, but has been linked through the food chain from plants to waterfowl to predators. A cyanobacterium is possibly the root cause.
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2015 NC Wildlife Action Plan
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