The Noble Research Center, OSU

This blog focuses on window strike mortality of birds at a single building on the campus of Oklahoma State University in Stillwater, OK. The Noble Research Center (NRC) is a large, irregularly shaped building that presents expanses of glass on its north and south sides, as well as recessed alcoves on the east and west through which vegetation inside the building can be seen from the outside. Thus, all surfaces of the building present a hazard to migrating birds.

Preliminary examinations of this building reveal essentially zero window killed birds during summer and winter and no resident birds among the casualties. Instead, mortality peaks for several weeks during spring and fall migration, and the casualties are almost all migrant birds in passage.

I surveyed this building approximately daily from mid-April to mid-May in 2009, and was surprised by the species composition and number of individuals found. For example, I found dead Yellow and Nashville warblers, Grasshopper and Clay-colored sparrows, and Indigo Buntings. These are all common migrants in the area, but the NRC is located in an urban setting, with very little vegetation suitable for any of these species in the immediate vicinity. The dead represent birds migrating through at night, and perhaps mistaking the vegetation reflected in the windows as appropriate places to stop after a night of migratory flight. The most surprising find of the Spring 2009 window kills was a Cassin’s Sparrow – a species that normally occurs in the state about 3 hours west of Stillwater.

Clay-colored Sparrow