Monkeys in country parks are to be sterilised to tackle the booming primate population and stop them straying into urban areas in the New Territories.
Veterinarians aim to begin rounding up monkeys next month to sterilise them by injection. The trial will target a clan of monkeys in the Kam Shan Country Park.
Monkey numbers in the New Territories have been growing at between five and eight per cent a year and could reach more than 2,000 in five years, the Agriculture, Fisheries and Conservation Department said.
About 1,400 monkeys live in country parks such as Kam Shan, Lion Rock, Tai Mo Shan, Tai Po Kau and Shing Mun.
The monkeys - to be rounded up in batches of about 20 at a time - will be injected on the spot and then released back to the clan about two to three hours after the effect of anaesthesia wears off.
Treated monkeys' ears will be notched with microchips attached for identification.
David Burrows, a senior veterinary surgeon from the department, said the monkeys' sex lives would not be affected by the treatment, which carried no side effects.