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Evidence of absence (v2.0) software user guide

July 6, 2017

Evidence of Absence software (EoA) is a user-friendly software application for estimating bird and bat fatalities at wind farms and for designing search protocols. The software is particularly useful in addressing whether the number of fatalities is below a given threshold and what search parameters are needed to give assurance that thresholds were not exceeded. The software also includes tools (1) for estimating carcass persistence distributions and searcher efficiency parameters (𝑝 and 𝑘) from field trials, (2) for projecting future mortality based on past monitoring data, and (3) for exploring the potential consequences of various choices in the design of long-term incidental take permits for protected species. The software was designed specifically for cases where tolerance for mortality is low and carcass counts are small or even 0, but the tools also may be used for mortality estimates when carcass counts are large.

Publication Year 2017
Title Evidence of absence (v2.0) software user guide
DOI 10.3133/ds1055
Authors Daniel Dalthorp, Manuela M. Huso, David Dail
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Data Series
Series Number 1055
Index ID ds1055
Record Source USGS Publications Warehouse
USGS Organization Forest and Rangeland Ecosystem Science Center