A migrant bird is pictured at Juyanhai wetland in Ejina Banner of Alxa League, north China's Inner Mongolia Autonomous Region, April 13, 2022. (Xinhua/Peng Yuan)
BEIJING, July 6 (Xinhua) -- Chinese and foreign researchers have for the first time revealed the migration routes and phenology of Beijing swifts, publishing their findings in the journal Movement Ecology.
The Beijing swift, or the Apus apus pekinensis, is a typical cavity-nesting bird that often nests inside holes and crevices in old buildings.
From 2014 to 2018, researchers from China, Sweden, Britain and Belgium fitted light level geolocators to 66 Beijing swifts to record light intensity along their migratory journey and track their position based on diurnal variation.
The light intensity data obtained from 25 swifts showed that they started to leave Beijing and fly toward the northwest in mid-July, and reached Central Africa in early September. They then slowly moved southward and finally arrived on the South African Plateau in early November.
After the Beijing swifts overwintered on the plateau for approximately 100 days, they began to fly northward rapidly in mid-February, left Africa in early April and returned to Beijing in late April.
The results revealed that the swifts undertake a round-trip journey of nearly 30,000 kilometers each year, flying over 37 countries in Asia and Africa. Their flight tracks indicated that they usually follow a direct migration route and move faster in the spring.
Researchers also concluded that the annual precipitation in the breeding and overwintering areas of Beijing swifts is significantly lower than that preferred by common swifts distributed across Europe. Beijing swifts are more adapted to semi-arid habitats and dry climate zones.
In the future, the research team will use genome sequencing technology to conduct genetics studies of the migration of Beijing swifts. ■