Skip to Content
Report an accessibility problem

Bird Censuses

Bird Censuses

Bird census map
Urban areas are expanding and intensifying worldwide, resulting in modified wildlife habitat where native vegetation is replaced by structures, roads, and other urban features. Although many species of wildlife inhabit and may even thrive in urban environments, the density of bird species appears to be highly responsive to alteration of land cover in addition to being reduced in cities relative to surrounding areas. However, the effects of urbanization on biodiversity are only minimally documented as long-term datasets reporting temporal changes in species composition and species gains and/or losses are required. In fact, many urbanization studies substitute time for space in an attempt to document impacts of urbanization through time.

Over the past half-century, the greater Phoenix metropolitan area has been one of the fastest growing regions in the US, experiencing rapid urban expansion in addition to urban intensification. This backdrop provides an ideal setting to monitor biodiversity changes in response to urbanization, and the CAP LTER has been using a standardized point-count protocol to monitor the bird population in the greater Phoenix metropolitan area and surrounding Sonoran desert region since 2000. The point count locations span a diversity of habitats including urban, suburban, rural, industrial areas, parks, agricultural fields, and native Sonoran desert. Many monitoring locations are co-located with other CAP LTER long-term monitoring programs, such as the Ecological Survey of Central Arizona, ground-dwelling arthropod monitoring, and Salt River Biodiversity, allowing investigators to leverage data from multiple monitoring efforts. Censuses are conducted in the winter and spring to capture the bird community at the peaks of activity, and each birding location is visited by three different professional birders each season who identify all birds seen and heard in the sampling radius.



Warren, P. S., S. B. Lerman, R. Andrade, K. L. Larson and H. L. Bateman. 2019. The more things change: Species losses detected in Phoenix despite stability in bird–socioeconomic relationships. Ecosphere 10(3):e02624. DOI: 10.1002/ecs2.2624. (link )

Allen, D. C., H. L. Bateman, P. S. Warren, F. Suzart de Albuquerque, S. Arnett-Romero and B. Harding. 2019. Long-term effects of land-use change on bird communities depend on spatial scale and land-use type. Ecosphere 10(11):e02952. DOI: 10.1002/ecs2.2952. (link )

Banville, M. J., H. L. Bateman, S. R. Earl and P. S. Warren. 2017. Decadal declines in bird abundance and diversity in urban riparian zones. Landscape and Urban Planning 159(Mar):48-61. DOI: 10.1016/j.landurbplan.2016.09.026. (link )

Lerman, S. B., V. K. Turner and C. Bang. 2012. Homeowner associations as a vehicle for promoting native urban biodiversity. Ecology and Society 17(4):Art. 45. (link )

Lerman, S. B. and P. S. Warren. 2011. The conservation value of residential yards: Linking birds and people. Ecological Applications 21(4):1327-1339. (link )

Shochat, E., S. B. Lerman, J. M. Anderies, P. S. Warren, S. H. Faeth and C. H. Nilon. 2010. Invasion, competition, and biodiversity loss in urban ecosystems. BioScience 60(3):199-208. DOI: 10.1525/bio.2010.60.3.6. (link )

Walker, J. S. and E. Shochat. 2010. Scalar effects of vegetation on bird communities in an urbanizing desert ecosystem. Urban Ecosystems 13:155-167. DOI: 10.1007/s11252-009-0112-0. (link )

Walker, J. S., R. C. Balling, J. M. Briggs, M. V. Katti, P. S. Warren and E. A. Wentz. 2008. Birds of a feather: Interpolating distribution patterns of urban birds. Computers, Environment and Urban Systems 32(1):19-28. DOI: 10.1016/j.compenvurbsys.2007.02.001. (link )