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Wildlife Health

Scientists draw blood from an elk for testing.
Wildlife Health Team and cooperators take blood samples from an elk in Rocky Mountain National Park, Colorado.

One component of the National Park Service (NPS) mission is to conserve the "wild life" within its units. To the NPS, wildlife includes everything from mega-fauna, such as bears and moose, to the smallest organisms, such as bacteria and protozoa. Native pathogens that cause diseases may be part of a naturally functioning ecosystem that is protected within a park. However, more frequenly wildlife are victims of diseases introduced by human activities. In these cases prevention and management are often necessary. Wildlife and ecosystem health are key components of the "One Health" concept, which recognizes that human and animal health are inextricably linked and that a holistic approach is needed to understand, protect, and promote the health of all species.

Wild animal populations are affected by diseases of all types, every day. Prevention of exotic disease introduction, for example from contact with domestic animals or translocation of wildlife, is preferred to management of an established disease. A few wildlife diseases that are currently of concern in units of the National Park System are white-nose syndrome, rabies, plague, tularemia, bighorn sheep pneumonia complex, chronic wasting disease, bovine brucellosis, epizootic hemorrhagic disease, chytridiomycosis, avian botulism, and West Nile virus. The threat of introduction of diseases not currently in the United States, such as foot-and-mouth disease and highly pathogenic avian influenza, are also of concern. Learn more about these diseases »

Key Principles of Wildlife Health Management

In general, natural processes are relied upon to maintain native animal species and to influence natural fluctuations in populations of these species; however, human impact that alters natural processes today is found even in the most remote areas. The key principles that the National Park Service employs to determine if a disease is managed or if it is allowed to self-regulate in wild animals include:

  • Is the disease native or exotic? If the host population has evolved in concert with the disease organism and the pathogen is native to the area and functioning naturally, the disease and its host will generally be left unmanaged. If, however, the disease was introduced or its occurrence was altered as a result of human influence, then it may be managed. Management options may include disease eradication.
  • Is management of the disease prudent and feasible? If so then the disease may be managed if:
    • The disease is a threat to human health.
    • The disease poses a risk to threatened or endangered species.
    • The disease threatens areas outside of the park.
    • The native disease is acting under unnatural conditions that would change the biology and epidemiology of the disease and is therefore a threat to ecosystem health.

After considering these questions, the appropriate management action may be clear. In other cases the National Environmental Policy Act (NEPA) is used as a decision-making tool to evaluate potential alternatives and to garner public input.

Last Updated: January 23, 2013