A recent study conducted by UCSB’s National Center for Ecological Analysis and Synthesis (NCEAS) found that urban environments are more supportive of biodiversity than previously thought, with a surprising number of animal and plant species thriving in these areas.
With funding from the National Science Foundation, researchers at NCEAS compiled a comprehensive dataset of the numbers of birds living in 54 cities around the world and plants in 110 cities. Collectively, the data indicated that species endemic to a given geographic location continue to flourish despite increasing urbanization. Additionally, it found that preserving some areas of green vegetation in cities is integral to maintaining the populations of these native species. One of the major findings maintain that even when some species experience a decline in numbers or disappear altogether from a city, other species may replace them and thrive in that same city.
Frank La Sorte, co-author of the study and a research associate at the Cornell Lab of Ornithology, pointed to New York City — one of the largest cities in the U.S. — as one city with the capacity to support a large bird population due to the presence of Central Park.
“New York City’s Central Park is a hotspot for migration,” La Sorte said. “Most of these birds are migrating at night and moving into the city. And when the sun comes up, they go into the forest that they’re in to roost during the day and they’ll continue their journey the next night.”
Cities that are filled with more natural habitat and green vegetation are generally able to not only support more bird and plant species but also sustain that biodiversity.
According to Madhusudan Katti, an associate professor in the Department of Biology at California State University, Fresno, cities in tropical locations offer a notable example of this phenomenon.
“What we find is that the tropical cities have more bird species, but then tropics in general have more bird species,” Katti said. “The results are compounded by the fact that many of the tropical cities are still expanding and developing rapidly, and they’re close to biodiversity hotspots.”
According to Jo-Ann Shelton, a UCSB professor of classics with a specialty in attitudes toward animals in the ancient and modern world, the study focused on birds and plants because these species appear to flourish more in cities than do other animal species. Shelton also said this may be because the other animal species compete with human interests more than do birds and plants.
“Nowadays, people seem to be more sympathetic to animals, but that’s because we’re not trying to protect our food supply,” Shelton said. “I think it was a different kind of relationship [hundreds of years ago] because most people produced their own food. Most people lived on farms and didn’t want to have predators around.”
As for helping bird and plant species to continue to thrive in cities, La Sorte said the best way to do this is to encourage residents to garden and, if they have yards, to add greenery to them. These features, according to La Sorte, can help create a “larger track of vegetation” and will benefit wildlife.
“One way that I’ve seen some success is creating an initiative within the community, not based on state or city resources,” La Sorte said. “In the long run, I think it is easier to convince homeowners to make changes in their backyards than to convince political structures of those cities to make those changes.”
Catering to regional pride may be another way of convincing people to support urban habitats, according to La Sorte.
“One of the findings in the study is that the cities retain a lot of regional distinctness,” La Sorte said. “So one thing we talked about was supporting regional pride or national pride in their native birds and plants, and I think that might be a good motivating factor.”