Where have the spoonbills gone?
Development could be reason why the number of at-risk birds returning this winter fell 30pc
The number of endangered black-faced spoonbills returning to Hong Kong and Shenzhen for the winter fell almost 30 per cent this year.
The decline put the population of the large, white, water-migratory birds calling Deep Bay a winter home at a 10-year low, the Bird Watching Society said.
Just 252 birds were recorded, down from 351 last year. Their numbers on the mainland also dropped to 339 from 363.
One-fifth of the global spoonbill population used to flock to Deep Bay, sandwiched between Hong Kong and Shenzhen, as a key wintering site a few years ago. This year, only 9 per cent came, a society report said.
Rapid development along the coastal mainland might have disrupted migratory patterns, though a clear reason for the steep decline could not be pinpointed, the society's research manager, Yu Yat-tung, said.
"The birds must fly long distances and this requires lots of energy," Yu said.
"If they don't get proper rest or adequate food on the way, they usually don't make it."