The Purple Martin (Progne subis) is a local and generally uncommon to rare summer visitor in the western U.S. Once considered fairly common in California (Grinnell and Miller 1944), it has suffered population decline over much of its former breeding range (Remsen 1978, Airola and Williams 2008). It is currently designated as a species of special concern by the California Department of Fish and Game (Shuford and Gardali 2008). Most of the known California population nests in the northwestern portion of the state, but the species also nests at scattered locations throughout the state’s non-desert regions (Small 1994, Airola and Williams 2008). In the Central Valley of northern California, the Purple Martin is known to nest only at several urban locations around Sacramento (Airola and Grantham 2003, Airola and Kopp 2007). In interior northern California, the only recent known breeding locations are scattered in central Siskiyou and eastern Shasta counties, the latter including a regular population at Shasta Lake (Williams 1998, Airola and Williams 2008). The Shasta Lake population is large for the interior portion of California and has been monitored better than the other sites. Because of the Purple Martin’s wide distribution, low density, use of relatively inaccessible areas, and use of ephemeral, wildfire-created habitats (Airola and Williams 2008) its population trends are difficult to track. Therefore any information on local populations as an indication of the species’ overall trend is useful.