Copyright K. Shawn Smallwood 2006 BIOLOGICAL EFFECTS OF REPOWERING A PORTION OF THE ALTAMONT PASS WIND RESOURCE AREA, CALIFORNIA: THE DIABLO WINDS ENERGY PROJECT

WEST, Inc. (2006) reported on the first year of fatality monitoring in the Diablo Winds Energy Project, which replaced 169 vertical axis wind turbines with 31 larger horizontal axis wind turbines in the Altamont Pass Wind Resource Area (APWRA). WEST, Inc. also compared bird utilization and mortality in the project area to utilization and mortality reported by Smallwood and Thelander (2004) across the APWRA. West, Inc. concluded mortality declined after Diablo Winds even though raptor utilization of the area increased. I reviewed the WEST, Inc. report, other reports of bird utilization and mortality at other wind farms, and I analyzed the Smallwood and Thelander data collected at the 169 wind turbines that were replaced.