Avian Abundance Patterns in Relation to the Distribution of Small Urban Greenspaces

摘要

Small urban greenspaces, such as neighborhood parks and private gardens, have often been overlooked or considered unlikely habitat sources owing to their small size, even though they may still provide important nesting and food resources for common songbirds. The objective of this study was to determine the role of small greenspaces, comprising a variety of land-use types, by assessing the distribution and abundance of four common songbird species. Point count data collected by the Baltimore Ecosystem Study were analyzed for four common urban songbirds: American robin (Turdus migratorius), northern cardinal (Cardinalis cardinalis), house sparrow (Passer domesticus), and European starling (Sturnus vulgaris). Vacant land, small parks, and residential land cover within a 200 m radius for each point count location were calculated as a proxy for private lawns and gardens,. Abundance modeling was conducted to determine which land-cover types best predicted the abundance values of each species and the distribution of each species across the city was mapped. American robin abundance was positively associated with small parks and negatively associated with vacant land, indicating that some form of greenspace management might be necessary for American robin use, specifically for foraging in short grass or nesting in younger trees. European starlings were negatively associated with small parks and had the greatest occurrence probability within the densely developed areas of downtown Baltimore. Results from this study can inform landscape planners of the benefits of certain spatial configurations and land uses that could increase urban biodiversity and sustainability. (C) 2015 American Society of Civil Engineers.