Population Study of Golden Eagles in the Altamont Pass Wind Resource Area: Second-Year Progress Report

This report details the results of field studies conducted from November 1994 through August 1996 in the Altamont Pass. This report updates and supplements the first year's report (NREL/TP-441-7821). The primary focus of the research is to quantify the effect of turbine-related mortality on the golden eagle population. To do this, the research must result in the quantification of both survivaland reproduction. To estimate the survival rates of both territorial and non-territorial golden eagles, 179 individual birds were tagged with radiotelemetry transmitters. Weekly surveys by airplane were conducted to locate the tagged eagles in relation to the WRA and monitor their survival. To estimate the reproductive rate, 74 territorial pairs of golden eagles were observed in the study areaand their reproductive outcomes were determined. The final report on this research project will incorporate the estimates of survival and reproduction to predict the effect of WRA mortality on population age structure.