Field manual of wildlife diseases: General field procedures and diseases of birds
No abstract available.
Information and Technology Report↗
Geology topics
Milton Friend
Publications and source records attributed to Milton Friend.
Waterfowl diseases: Causes, prevention, and control
Preventing and controlling disease in waterfowl is a difficult job. Few tools are available to deal with disease in highly mobile, unconfined animal populations, and few managers are trained and experienced in the prevention and control of avian diseases. Furthermore, the geographic distribution, frequency of occurrence, magnitude of losses, and causes of diseases in waterfowl, as in other life forms, change over time. Waterfowl mortality from infectious diseases, for example, has increased in the past 20 years (Friend 1992).
Report↗
Increased avian diseases with habitat change
Changes in disease patterns and trends reflect changing relationships between the affected species (host) and the causes of disease (agent). Host-agent interactions are closely linked to environmental factors that either enhance or reduce the potential for disease to occur. As a result, wildlife disease patterns and trends are, to a substantial extent, indicators of environmental quality and changing host-agent interactions within the environment being evaluated. The types, distribution, and frequency of diseases causing major avian die-offs have changed greatly during the 20th century. Too little is known to assess the changes of most avian diseases that result in chronic attrition rather than major die-offs, or about those that affect reproductive success, reduce body condition, or affect survival in other indirect ways. Nevertheless, the changing patterns and trends in highly visible avian diseases provide notice of problems needing attention. Information on the status of disease in wild birds was obtained from National Wildlife Health Center (NWHC) evaluations of the cause of death for more than 30,000 carcasses from across the United States during the past two decades, reports of avian mortality received from collaborators, the scientific literature, and NWHC field investigations of bird mortality. Comprehensive assessments of causes of wild bird mortality, magnitude of losses, and geographic distribution of specific diseases are not possible from these data, although we can identify general relationships for waterfowl and some other species.
Book chapter↗
Control of avian influenza: Philosophy and perspectives on behalf of migratory birds
Aquatic birds are considered the primary reservoir for influenza A viruses (Nettles et al., 1987). However, there is little concern about avian influenza among conservation agencies responsible for the welfare of those species. IN contrast, the poultry industry has great concern about avian influenza and view aquatic birds as a source for infection of poultry flocks. In some instances, differences in these perspectives created conflict between conservation agencies and the poultry industry. I speak on behalf of migratory birds, but philosophy and perspectives offered are intended to be helpful to the poultry industry in their efforts to combat avian influenza.
Avian Diseases↗
Introductory remarks: Disease ecology and the conservation of avian species
No abstract available.
Acta XX Congressus Internationalis Ornithologici↗
Lead poisoning: The invisible disease
Lead poisoning is an intoxication resulting from absorption of hazardous levels of lead into body tissues. Lead pellets from shot shells, when ingested, are the most common source of lead poisoning in migratory birds. Other far less common sources include lead fishing sinkers, mine wastes, paint pigments, bullets, and other lead objects that are swallowed.
Fish and Wildlife Leaflet↗
Avian cholera: a major new cause of waterfowl mortality
No abstract available.
Fish and Wildlife Leaflet↗
Avian botulism: geographic expansion of a historic disease
Avian botulism is a paralytic, often fatal disease of birds resulting from ingestion of toxin produced by the bacterium Clostridium botulinum. Waterfowl die-offs from the botulism are usually caused by type C toxin; sporadic die-offs among fish-eating birds, such as common loons (Gavia immer) and gulls, have been caused by type E toxin.
Fish and Wildlife Leaflet↗
Disease control operations
Individual disease outbreaks have killed many thousands of animals on numerous occasions. Tens of thousands of migratory birds have died in single die-offs with as many as 1,000 birds succumbing in 1 day. In mammals, individual disease outbreaks have killed hundreds to thousands of animals with, for example, hemorrhagic disease in white-tailed deer, distemper in raccoon, Errington's disease in muskrat, and sylvatic plague in wild rodents. The ability to successfully combat such explosive situations is highly dependent n the readiness of field personnel to deal with them. Because many disease agents can spread though wildlife populations very fast, advance preparation is essential in preventing infected animals from spreading disease to additional species and locations. Carefully though-out disease contingency plans should be developed as practical working documents for field personnel and updated as necessary. Such well-designed plans can prove invaluable in minimizing wildlife losses and costs associated with disease control activities. Although requirements for disease control operations vary and must be tailored to each situation, all disease contingency planning involved general concepts and basic biological information. This chapter, intended as a practical guide, identifies the major activities and needs of disease control operations, and relates them to disease contingency planning.
Report↗
Interpretation of criteria commonly used to determine lead poisoning problem areas
Determination of lead poisoning problem areas is complicated by the nature of the disease process. Rigorous documentation of lead poisoning as a cause of mortality in birds requires the integration and evaluation of pathological and toxicological data by an experienced diagnostician. No single technique provides unequivocal proof that lead exposure occurred at the site of death. However, evaluation processes that integrate knowledge regarding the course of lead poisoning in birds, bird movement patterns in specific geographic areas, and findings from studies involving criteria commonly used to measure exposure to lead shot provide a sound basis for determination of specific problem areas. Sequential sampling during the period of bird use is an important requirement for establishing strong cause and effect relations. Knowledge of lead poisoning characteristics as a disease process are also useful in identifying lead poisoning problem areas.
Fish and Wildlife Leaflet↗