This study was conducted as part of PG&E's performance monitoring program for a Boeing MOD-2 wind turbine located on the western edge of Suisun Marsh in Solano County, California.
Raptor and waterfowl movements were monitored prior to construction. Nocturnal migration over the site was monitored for 6 weeks using a portable ceilometer-image intensifier system. Searches for dead birds were conducted 5 days a week during this period and once weekly thereafter. Weather data were collected to determine the relationship between bird movements and weather conditions. Findings reported include low rates of waterfowl movement and nocturnal passerine migration over the site; moderate to high raptor use of the area; collisions occurring during all lighting and weather conditions; and insignificant collision mortality. Five dead birds were found between fall 1982 and January 1, 1983, including a warbler, a meadowlark, a starling, a coot, and an American kestrel. The paper includes an account of the authors watching an American kestrel interacting with an operating turbine, finally being struck by the rotor and killed. EPRI (1985) presents results of the completed study.