Two conservation groups on Wednesday said Hong Kong's lenient pet trade regulations have made the city the world's top importer of exotic species.

WWF and the ADM Capital Foundation said a study they carried out has found that Hong Kong imported more than five million animals of exotic species between 2015 and 2021, with more than half of them under threat of extinction.

The demand for exotic pets was one of the main reasons, the groups said, even though such animals are very difficult to look after properly.

"We had 135,000 alligator snapping turtles imported legally into the city. But are there 135,000 people in Hong Kong who have the skill set, the facilities and the determination to actually look after an animal which becomes very unwieldy very quickly?" questioned Sam Inglis, the foundation's wildlife programme manager.

Christie Wong, wildlife programme officer at the foundation, said the government should tighten pet trade regulations.

"One of the main recommendations would be to set up a positive or negative list of approved species that can be traded or possessed, so that it'll be very clear to traders and people who want to buy pets," she said.

The foundation also urged the government to set up a system to keep track of exotic animals in the territory, to give them more protection.