Spatial distribution and the value of green spaces for urban red-tailed hawks

Raptors increasingly live and nest successfully in urban areas. In the urban landscape of Hartford, CT, red-tailed hawksestablished home rangesin large green spaces such as parks, golf courses, and cemeteries but also nested successfully in the commercial district of downtown and in densely built urban and suburban neighborhoods. Data collected from 11 radio-tagged breeding adult hawksindicated that year-round home rangesaveraged 107.7 ha, much smaller than home rangesreported for hawksinhabiting rural areas. Most hawk home rangeshad multiple core areas that were usually associated with favored perchesor larger patches of ‘usable’ green space, defined as patches ≥0.25 ha in size, and home rangesize was positively associated with larger usable green space patches in core areas. Most nests were located in the largest core area and were within a larger patch of green space within the largest core area. Rather than just the amount or size of green space patches, the value of urban green spaces for these hawkslikely also varies with the number and proximity of suitable perchessuch as buildings or tall trees, types and density of prey, and amount of human activity in and adjacent to these spaces. Territoriality and intraspecific competitionmay also influence home rangesize and dispersion of red-tailed hawksnesting in Hartford. In this urban area, mortality due to ingestion of rodenticidesand collisions with vehicles affected hawkreproductive success.