Seth has recently assisted in estimating bird, bat, and golden eagle mortalities at the first of several windfarms to better understand the impacts of wind energy on local and migratory wildlife populations. This included using the R packages ‘GenEst’ and ‘Evidence of Absence’, plus estimating eagle carcass persistence times using surrogate data and calculating carcass size class density weighted proportions (‘dwp’, a required but difficult-to-estimate model parameter) of the number of carcasses expected to fall within the search area. Properly estimating model parameters and estimated mortalities is a critical component of windfarm monitoring and compliance.