Hong Kong has been urged to enact new legislation to ensure bird-friendly building designs, after an NGO found that more than 280 birds had died in window collisions between 2022 and 2023.
High-rises with extensive glass may pose “fatal traps” for migrating birds, the Hong Kong Bird Watching Society (HKBWS) said on Thursday in its report on bird-window collisions in the city.
Between September 2022 and August 2023, the NGO recorded 249 cases across 16 districts in Hong Kong. A total of 284 birds died and 25 were injured. There were also 69 imprints, such as feather dusts, feathers, or excrement left on the glass after the collision.
Peak month
November was the peak month of bird collisions, with seven group collision cases recorded month in 2022. The biggest incident involved 35 Chinese Bulbuls, which were found dead after a suspected collision at Wu Yee Sun College, Chinese University of Hong Kong on November 10, 2022. It was likely due to the autumn migration and wintering season, the NGO said.
Migrating birds accounted for over 60 per cent of collision victims, while critically endangered yellow-breasted bunting and Class II National Protected Species such as the northern boobook and bluethroat were also among the dead and injured birds.
“Hong Kong attracts tens of thousands of migratory birds to stopover and refuel energy every year… But at the same time, Hong Kong being a high-density city and the high-rises with extensive glass may unfortunately turn out to be fatal traps for migrating birds,” the 52-page report read.
‘Misleading visual cue’
According to the NGO, birds colliding with high-rise buildings were likely flying long distances at greater heights in Hong Kong. They may have mistaken the light-reflecting glass facades as the skyline or landscape, leading to collisions.
Birds may also collide with shorter structures due to their close proximity to nearby trees and other vegetation. The researchers explained that glass coverage on these buildings may create a “misleading visual cue” for birds by reflecting images of the surrounding greenery.
(Disturbing image) – click to view.
Woo Ming-chuan, deputy director of HKBWS, said that collision risk could be reduced if the distance between buildings and bird habitats was taken into consideration during site selection. New buildings should also prioritise reducing glass coverage, she said.
New laws
The NGO called on the government to establish legislation requiring new buildings to implement bird-friendly designs. Examples form overseas showed that designing such laws was feasible, Woo said.
Existing glass structures should also be improved by installing collision prevention markers on external glass surfaces, allowing them to be seen by birds, the NGO suggested.
It cited the installation of bird collision prevention stickers at Mei Foo MTR Station, saying that the collision rate was reduced by 90 per cent afterwards.
The government should also “take the lead” in adopting these prevention measures at known high-risk buildings, the group said, as individual departments – including the Highways Department – had added prevention patterns to some of its transparent roadside noise barriers.
(Disturbing image) – click to view.
“Through site selection, site planning and building design, it is possible to [protect] the wild birds against unnecessary harm and to respond to the global challenge of biodiversity loss,” Woo said.
