Land use, scale, and bird distributions in the Phoenix metropolitan area: Fid-Bau Portal

Land use, scale, and bird distributions in the Phoenix metropolitan area

Hostetler, Mark / Knowles-Yanez, Kim

AbstractMost urban areas have land use maps, but these maps have not been used to explore whether land use categories affect bird distributions. We explored how land use, at 10 different scales, affected the distribution of bird species surveyed in the Phoenix metropolitan area during the breeding season. Based on vegetation cover and built structure, we randomly established 30, 1km transects located in older residential neighborhoods, younger residential neighborhoods, remnant desert areas, and golf courses. Each transect was divided into five 200m segments, and we surveyed transects between 1 May and 31 July 1998. From Maricopa Associations of Governments (MAG) land use data, we measured the amount of different land uses surrounding each segment from a small circular buffer, 100m radius, to a large circular buffer, 2500m radius. For each buffer area and species, we conducted multiple regressions between average bird counts and percent area represented by each land use category. Across all scales, results demonstrated that only 4 of 26 species had a significant coefficient of multiple determination >0.5 between average bird counts and land use. For most species, these results indicate that land use, as defined by MAG, has limited predictability on the number of birds found in an area. We hypothesize that the structural design of given area (e.g. quantity and types of trees planted) probably plays a primary role in affecting the distribution of most bird species in urban environments. Thus, regardless of land use designation, landscape design and management of an urban area may strongly influence whether an area is attractive to a given bird species.