鸟类能给城市带来经济活力

Is it worth having birds in the city? If you live in Seattle or Berlin, the answer is yes, to the tune¹ of $120 million and $70 million a year for each city, respectively.   A new study published last month in the journal Urban Ecosystems² tries to determine what economic value residents in two comparable cities place on having birds in their backyards and parks. Researchers at the University of Washington and Humboldt State University compared two types of common birds -- finches and corvids -- in both cities, asking residents how much they would pay to conserve³ the species and what they spend, if anything, on bird food.   They found that both cities place a "sizeable" value on bird enjoyment⁴, somewhat more so in Seattle. Residents in both cities spend more than the average U.S. adult on bird-supporting activities, suggesting that people from Seattle and Berlin value having birds around their homes and neighborhoods more than in most cities.   These activities, in turn, also show that birds benefit the local economies as residents invest in food and nesting structures.   "This paper shows that our interactions with birds actually have a pretty high economic return to the community where you live," said John Marzluff, a UW professor of environmental and forest sciences and the paper's co-author. "We know that having a livable, green community that attracts birds also increases the value of homes in that area. This paper shows there's an economic service birds are providing."   Researchers say this is the first look at estimating the economic value of enjoying common birds in an urban setting. Previous studies have assessed people's willingness to pay to see rare or charismatic birds and to pay for conservation of endangered species, but these instances don't affect most people.   "No one has really looked at what people will be willing to pay for these more common species, ones that aren't necessarily endangered or threatened. We wanted to address that because people living in urban areas don't encounter endangered species on a daily basis," said co-author Barbara Clucas, a lecturer at Humboldt State University who completed this study as a postdoctoral researcher at the UW.