Nest boxes in Hong Kong offer lifeline for endangered cockatoos

Hong Kong — Critically endangered yellow-crested cockatoos have found a growing foothold in the city’s parks and campuses, where researchers are installing artificial nest boxes to replace lost natural hollows in aging trees. On the University of Hong Kong campus, a pair has already settled into a wooden box fixed to a tree, researchers said. Astrid Andersson, a HKU postdoctoral researcher who leads the effort, said the team plans to install 10 boxes by the end of the year and eventually pursue about 50 across Hong Kong Island so the birds can continue living amid the city’s skyline.

Native to Indonesia and East Timor, the snow-white cockatoo with a yellow crest accounts for roughly 10% of the global wild population, which totals about 2,000 mature birds. But Hong Kong’s urban cockatoos face shrinking nesting opportunities as natural hollows in aging trees disappear after typhoons and routine tree trimming for public safety. The pressures add to global threats, including the illegal pet trade and climate change. The International Union for Conservation of Nature says as much as 90% of the species’ population has disappeared since 1978, largely due to trapping for the pet trade. Indonesian authorities have struggled to enforce the 1994 export ban, and trafficking continues; in 2015, police arrested a man suspected of smuggling about 20 birds by hiding them in water bottles. Deforestation in Indonesia has been extensive; Global Forest Watch estimates the country lost about 107,000 square kilometers of tropical rainforest between 2002 and 2024 — an area roughly the size of Iceland — and the loss accounts for about a third of all tree-cover loss during that period. Climate change is intensifying drought and fire risk on volcanic islands. Bonnie Zimmermann, director of the Indonesian Parrot Project, said, “The fires are humongous.”

Many of the birds seen in Hong Kong parks may be escapes or released pets rather than wild natives. An urban legend holds they descended from birds released by a British governor when Hong Kong surrendered to invading Japanese troops in 1941. Hong Kong bans commercial trade in wild-caught cockatoos but allows captive-bred sales for operations registered under CITES; however, no such breeding operation is currently registered in the city. A 2017-2018 survey by Andersson’s team found 33 cockatoos for sale in the city, about three times the number imported since 2005, according to HKU’s statement. In August, a three-month-old chick in the city’s bird market was priced at 14,000 Hong Kong dollars (about $1,800). The market questions the origin of many birds, the university noted.

Andersson said she has developed a forensic test to help distinguish wild birds from those bred in captivity and hopes it could be applied in the market someday. She also plans to deploy cameras inside the nest boxes to collect data on cockatoo reproductive behavior, a topic not widely studied. The project is part of broader efforts at HKU and local conservation groups to keep the urban birds from disappearing.

Conservationists say Hong Kong’s cockatoos symbolize the potential for coexistence between people and wildlife in a dense urban environment. Local genetic lineages in Hong Kong could differ from those in the birds’ native range, potentially contributing to the species’ genetic diversity. “Hopefully, Hong Kong’s population will be able to contribute to saving this species from extinction,” Andersson said.

Harry Wong, a conservationist who helped install a nesting box in Causeway Bay, said his effort a decade ago met with little success, but this time he has seen a pair occupy a box within two months. “We can create small things in the city that allow the animals who live here to coexist with us,” he said.

Experts caution that the nest-box approach is not a substitute for wide-scale habitat protection and stronger enforcement against illegal trade, but it can buy time for a species under pressure while longer-term measures are pursued.

Public awareness remains a challenge. Dreamy Cheung, who bought a pet cockatoo named Mochi in 2021 for about 20,000 HKD, says she was unaware of the bird’s endangered status until later. Cheung said the lack of identification and uncertain origin heightened her worry about the bird’s future and the possibility of illegal origins. The Agriculture, Fisheries and Conservation Department said in a statement that the government is committed to protecting endangered species, with regular market inspections and shops that sell birds. It noted it has no record of cockatoo poaching in the past five years but will investigate any reports and will provide advice on bird-conservation measures when tree trimming may affect wild birds.