Fig. 1.

Locations of 82 bird survey sites in both geographical and climatic space. (A) Geographical locations of cross-sectional resurvey transects through the Sierra Nevada superimposed onto topography of California (higher elevations in lighter gray). Locations of neighboring survey sites (red circles) have been aggregated to provide visual clarity. The number of sites per transect from south to north are: Southern Sierra, 25; Yosemite, 24; Interstate 80, 3; and Lassen, 30. (B) Locations of resurvey sites in climate space, with arrows pointing from historical breeding season climate to modern breeding season historical climate. Color codes correspond to transect: Southern Sierra in blue, Yosemite in orange, Interstate 80 in purple, and Lassen in green.