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Mortality investigation

January 27, 2015

Wildlife mortality events usually occur unannounced and may find management agencies unaware. These events can become highly visible and politically charged affairs, depending upon the scale or species involved. The public, media, and (or) politicians may pressure managers, field investigators, and diagnosticians to quickly identify the cause or to comment on potential causes, the significance of the event, what is being done about it, and a resolution. It may be common during such events for speculation to rage, and for conflicting theories to be advanced to explain either the environmental conditions that led to the mortality or the actual cause of death.

The overarching goal of a wildlife mortality investigation is to determine what happened and to identify causative factors that may have led to the event. Steps include obtaining the relevant history (defined later), conducting on-site field evaluations when necessary, collecting suitable samples, and completing appropriate diagnostic laboratory analyses. These procedures allow diagnosticians and biologists to determine the potential cause of mortality as swiftly as possible, or at the very least, to systematically eliminate potential causes of mortality so as to allow managers to focus on the most probable cause.

Investigating mortalities in free-ranging wildlife poses a series of challenges requiring careful preparation, clear evaluation of objectives, and flexible implementation.

Citation Information

Publication Year 2015
Title Mortality investigation
DOI 10.3133/tm15B3
Authors Thierry M. Work
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Techniques and Methods
Series Number 15-B3
Index ID tm15B3
Record Source USGS Publications Warehouse
USGS Organization National Wildlife Health Center

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