A recent survey has found that more Beijing Swift nests are located in modern buildings, such as flyovers, with no particular preference for ancient architecture as before, indicating that the birds are gradually adapting to urbanization.
The Beijing Swift is an iconic bird synonymous with the capital city since ancient times. The migratory birds were usually found nesting in high buildings with eaves such as city gatehouses and imperial garden buildings. They can be seen at the Forbidden City, the Lama Temple and the Summer Palace from mid-April to July every year.
Previous studies showed that the bird's population in the city declined due to the loss of nest sites caused by the replacement of traditional-style buildings with new buildings that lack the holes for them to breed.
The new survey was conducted for 17 weeks this summer by scientists from the Beijing Wildlife Rescue and Rehabilitation Center with the participation of 300 volunteers. They discovered that the number of swifts in Beijing was about 7,005, nearly the same as last year.
Among 71 nesting sites, the most populated area is the Tianning Temple Bridge on the West Second Ring Road, where they found a total of 663 swifts. Other modern buildings including the Beijing West Railway Station and the Poly Plaza on the East Second Ring Road have new nests.
"It shows that the birds have stable living conditions in Beijing. In addition, the growing population of swifts around modern buildings suggests that they are adapting to the city's changes," said Shi Yang, researcher of the center and lead of the swift survey, at a meeting by the Beijing Wildlife Conservation Association.
In 1870, the birds were first described by a British naturalist as a subspecies of the common swift named the Beijing Swift. Ornithologists see swifts as "supreme aerialists" with very narrow long wings, ranking them among the fastest animals on the planet, spending most of their lives in the air.
Because they seldom land on the ground and are so fast and aerial, swifts are very hard to study. "We know very little about the bird," Shi said.
Traditional breeding sites of Beijing Swifts are the eaves of pavilions and gatehouses, which have been mostly torn down to make way for skyscrapers and wider roads.
To protect the swifts, some Chinese property developers, together with environmental NGOs, have recently committed to making new buildings more bird-friendly by having swift nesting places in the design.
The swifts are a health monitor of the city. "Countries such as Germany, the United States and Israel have decades-long bird surveys around the urban environment changes," said Zhao Xinru, a professor of zoology at Beijing Normal University.
"We need to keep investigating the birds so that we can have enough data to study and protect them."