Chapter 5 Threats
populations to determine impacts are needed before appropriate management strategies can be developed.
5.13.3 Crayfishes – Anticipated Impacts Relatively little published research is available concerning crayfish diseases and much of the work is from Australia and Europe. Edgerton et al. (2002) provide a synopsis of crayfish diseases and pathogens. Most disease agents (viruses, bacteria, etc.) cause only limited impacts to crayfish (Longshaw 2011) . Disease in freshwater crayfish can result from abiotic factors such as adverse environmental conditions, poor nutrition, and exposure to waterborne toxicants or biotic factors such as viruses, parasites, or microorganisms (Edgerton et al. 2002) . Crayfish aquaculture production provides an opportunity to better monitor health status and detect pathogen and disease transmission because population densities allow efficient transfer of disease between individuals. 5.13.4 Mammals – Anticipated Impacts White-nose Syndrome (WNS) is a disease of hibernating bats that has spread from the northeastern to the central United States. Since the winter of 2007–2008, millions of insect- eating bats in 25 states and five Canadian provinces have died from this disease. The fungus Pseudogymnoascus destructans is known to cause WNS in hibernating and colonially roosting bat species. Current estimates of bat population decline in the northeastern United States since the emergence of WNS are approximately 80%. It is suspected that human use of caves is spreading the disease, so some jurisdictions have closed or limited entry to caves. Despite these precautions, the disease continues to spread. The ecological consequences of these declines are likely to impact agricultural operations because bats are primary consumers of insects. A recent economic analysis indicated that insect suppression services (ecosystem services) provided by bats to United States agriculture are valued at between $4 and $50 billion per year (USGS NWHC 2013) . Chronic Wasting Disease (CWD) is a disease of the nervous system in deer and elk (family Cervidae) that is characterized by spongy degeneration of brain tissue resulting in emaciation, abnormal behavior, loss of bodily functions, and ultimately death. There currently is no treatment for the disease, and it is typically fatal for infected animals. It is not known to infect livestock or humans at the present (USGS NWHC 2013) . The US Centers for Disease Control and the World Health Organization indicate there is no evidence that CWD can be transmitted to humans or linked to any neurological diseases of humans (NCWRC 2014) . According to the Chronic Wasting Disease Alliance, CWD has been confirmed in wild and captive cervids in numerous states and in Canada, including in North Carolina. The NCWRC has had a preventative disease management strategy since 2002, when rules were adopted to prevent the introduction of the disease and to minimize the spread of disease should it be found in the state. The strategy includes implementing administrative rules (15A NCAC 10B) on holding deer
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2025 NC Wildlife Action Plan
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