The U.S. Geological Survey (USGS) claims its newly created software can help owners and operators better estimate wildlife fatalities at or near wind farms.
According to the USGS, the software combines counts of animal carcasses and detection-rate information to estimate the number of fatalities and to provide measures of uncertainty of these estimates to help managers address concerns about the potential environmental effects.
Bird and bat fatalities at some wind power facilities have led to recommendations and sometimes requirements from state and federal regulators that facility managers monitor wildlife fatalities as a condition for facility development and operation. Typically, the monitoring involves searching for carcasses beneath or near wind turbines.
Unfortunately, notes the USGS, simple counts of dead animals do not reflect actual fatality because carcasses are detected at varying rates. Carcasses may be removed by scavenging animals before monitors are able to include them in count information.
Some species are inherently easier to detect than others. Further, carcasses can be obscured by vegetation or can fall in steep terrain that is difficult or impossible to search.
The software has its limitations, the USGS cautions. A different set of statistical tools is needed to evaluate fatality of a particular species, such as in cases of rare or endangered species, the agency notes.