Scientific insights and lessons learned from the 9 Year Monitoring Program in the Altamont Pass Wind Resource Area

A lawsuit over the high number of raptor fatalities in the Altamont Pass Wind Resource Area (APWRA) prompted Alameda County to institute the largest avian fatality monitoring program in the history of the wind industry. The... [ view full abstract ]

A lawsuit over the high number of raptor fatalities in the Altamont Pass Wind Resource Area (APWRA) prompted Alameda County to institute the largest avian fatality monitoring program in the history of the wind industry. The monitoring program lasted over 9 years (ending September 2014), and was overseen by a scientific review committee with representatives appointed by the County, the Wind Energy Industry, and environmental groups. Previous estimates of facility-wide fatalities were based on detection probabilities that were not measured, and different “guesses” about what those detection probabilities were lead to widely variable estimates and generated considerable controversy and confusion. Facility-wide fatality estimates from the most recent effort were based on detection probabilities that were actually measured, although estimates were produced using data collected from several studies implemented by the monitoring team over several years. Insights derived from this program with respect to sampling design, statistical rigor, and setting up and implementing a scientifically credible, responsible, and effective scientific oversight process have widespread applicability. In the end, the monitoring program produced a new paradigm for estimating detection probability, implemented several important ancillary studies including estimating the size of the burrowing owl population in the study area, assessing the role of background mortality factors, and shedding light on the relationships between raptor use, fatality rates, turbine size and type, and the effectiveness of shutting down turbines during the winter period when raptor use was highest.