Fish and Wildlife Disease

Chronic wasting disease (CWD) is an emerging infectious disease that is fatal to free-ranging and captive animals in Cervidae, the deer family. CWD is one member of a family of diseases called transmissible spongiform encephalopathies (TSEs), and is thought to be caused by prions. CWD is the only TSE known to affect free-ranging wildlife.

USGS researchers are working with partners to assess the health and foraging behavior of Florida manatees in the northern Indian River Lagoon and Banana River, areas that have experienced declining seagrasses due to an extended phytoplankton bloom.

This project is an effort to create spatially and temporally explicit models for waterfowl distribution across the United States for use in avian influenza transmission risk modeling.

Deaths of young-of-year smallmouth bass in the Chesapeake Bay drainage has been noted since 2005. Studies of affected fish have found bacterial, viral and parasitic infections. Mixed infections suggest these fish are immunosuppressed. Understanding the role of specific pathogens and environmental factors that contribute to their presence is important but equally important is the understanding of...

Introduced mosquito-borne avian diseases, avian pox and avian malaria, are key limiting factors for endemic Hawaiian forest birds and are, in part, likely responsible for past extinctions and the continued decline of extant species populations. In the last 40 years on the island of Kaua‘i a number of species have become increasingly rare and several are now presumed extinct. Coinciding with these...

Migratory birds, and particularly those using habitats close to human settlements, may be infected with antibiotic resistant bacteria. The USGS is working with public health professionals to understand the role of birds in the maintenance and dispersal of antibiotic resistant bacteria. Additionally, the USGS is investigating how antibiotic resistant bacteria in birds may relate to public and...

Avian influenza is a viral disease caused by various strains of avian influenza viruses that can be classified as low pathogenic avian influenza (LPAI) or highly pathogenic avian influenza (HPAI). It remains a global disease with potential high consequence with the potential to threaten wildlife, agriculture, and human health.

The USGS National Wildlife Health Center (NWHC) provides the following index of wildlife disease information resources as a starting point to learn about selected wildlife diseases.

Species Studied - Chinook Salmon ( Oncorhynchus tshawytscha )

CWD is a degenerative neurological disease caused by infectious proteins called prions. Although documented cases are invariably fatal, infected elk commonly survive for several months or longer, passing prions directly to other individuals and into the environment, where they bind to surfaces or soils and can persist for years. CWD reached Wind Cave National Park about 1997 and rapidly became the...

Interest in the immune systems of wild birds has increased as public health authorities have recognized that many emerging infectious diseases of wildlife can be transmitted to humans (i.e., zoonoses). Eco-immunology is an emerging field that characterizes how immune adaptations of wild species vary as a result of evolution in different habitats and niches. Present understanding of the influence...

Botulism is a natural toxin produced by a bacterium ( Clostridium botulinum ) commonly found in the soil. There are several types of botulism toxin some of which can affect humans who eat improperly canned foods. Birds get their own kind of botulism (Type C in Hawaii) that does not affect humans. Botulism type C is concentrated in aquatic invertebrates that filter feed sediments or water. When...