Breeding Bird Survey songbird occurrences during 1977-1979 and 2012-2014 in conterminous U.S.

Data used in: "Misleading prioritizations from modeling range shifts under climate change" by H.R. Sofaer, C.S. Jarnevich, and C.H. Flather. Breeding Bird Survey data (version 2014.0) for songbirds were summarized over historical (1977-1979) and recent (2012-2014) time periods at routes in the conterminous U.S. Avian occurrence data were combined with information on climate and land cover at each survey route.