Home sellers take note: That blue jay in your backyard could add $32,000 to your asking price. An innovative study of home sales in Lubbock, Texas, suggests that planners can use relatively simple bird counts to analyze the ecological and economic values of urban landscapes. And it finds that even a single extra species can help pinpoint relatively rich ecosystems.
“A problem urban ecologists and ‘new urbanists’ often face is the difficult task of completing ecological-environmental evaluations in a timely and cost-effective fashion,” write Michael C. Farmer and colleagues at Texas Tech University, Lubbock, in Urban Ecosystems. As a result, officials in a rush to issue permits often deem all green spaces, such as public parks, beneficial—even though ecologists know “that not all green spaces are equally valuable.”
The researchers decided to see whether bird surveys might offer a quick-and-dirty solution. They collected information on approximately 368 home sales in 17 Lubbock neighborhoods from 2008 to 2009. Then they conducted bird counts in the vicinity of each home sale, recording both the total number of birds and the number of “less-ubiquitous” species—which included blue jays and western kingbirds. They also used Google Earth to estimate the percentage of tree cover in the area surrounding each sale. Finally, they constructed a model that related bird abundance and species richness to home prices.
The model suggests that the presence of less-common birds helps home prices soar. On a lot that already had one less-common species, for instance, the addition of a second such species improved mean home prices by $32,028. Although that number shouldn’t “be taken too literally,” it does suggest that the presence of less-common birds indicates a varied ecosystem—such as one with a variety of trees and shrubs. That’s in line with ecological studies showing that more diverse bird life tends to inhabit ecosystems with more “vertical” diversity (vegetation of various heights).
“This deliberately simple and inexpensive indicator,” they conclude, could help ecologists and economists identify development practices that provide “even stronger gains to housing values, environmental footprint, and urban wildlife that might otherwise go unnoticed in a quick-paced development cycle.” ❧
–David Malakoff
Farmer, M.C., M.C. Wallace and M. Shiroya. 2011. Bird diversity indicates ecological value in urban home prices. Urban Ecosystems doi:10.1007/s11252-011-0209-0.
