Bird diversity indicates ecological value in urban home prices

Abstract

It is known that public greenspaces contribute positively to urban home prices; yet urban ecologists also have known that not all greenspaces are equally valuable. Also some ecologically valuable space appears on private residences, not only public spaces. This work examines directly whether using a variable derived from bird species richness and relative abundance adds new information regarding ecological value and if high values of that variable significantly improve urban housing prices. We collected information on approximately 368 home sales in Lubbock, TX from 2008 to 2009 from the Multiple Listing Service: Sale Price, Square Footage, Lot Size and Age in 17 neighborhoods identified by the Lubbock Realtor Association. We conducted bird counts in the vicinity of each home sale and recorded both the total numbers of birds and the number of bird species identified in a particular class—less ubiquitous bird species. Finally, we used GIS to record the percentage of tree cover in the immediate area surrounding each sale. We constructed a predictive model for a bird relative abundance and species richness variable (Bird) from AICc statistics. Home price for each sale then was regressed against the predicted value of ‘Bird’ from the selected model and regressed against home price along with other attributes from the Multiple Listing Service. The predicted value for Bird finds that the addition of another desirable, less ubiquitous bird species improves mean home price by $32,028, likely due to the human created landscapes on private properties immediately surrounding a home sale. Curiously, the presence of a nearby park neither explained variation in the ecological indicator nor contributed to home price elevation. This deliberately simple and inexpensive indicator helped to direct attention to the composition of local landscapes in specific areas to assess joint ecological and economic gains rather than presume a priori that open greenspace jointly satisfies these dual objectives.