A rare fish not seen in Hong Kong waters in modern times has been spotted by divers taking part in a fund-raising underwater mini-census. The sighting of the humpback grouper in waters off Sai Kung on Sunday was the highlight of the first annual Big Fish Count organised by the World Wide Fund for Nature (WWF). Four teams comprising 32 divers took part in the event and recorded 152 species of fish. All funds raised from sponsors will go to the WWF. Humpback groupers are a threatened species which Hongkongers normally only ever see in seafood restaurants, which import them from countries such as Indonesia and the Philippines. Paul Hodgson, who helped organise the count, said the sighting of the humpback grouper was the first recorded in modern times and a sign that Hong Kong's waters may be gradually recovering from the effects of over-fishing. 'The humpback grouper was suspected to exist in Hong Kong waters, but this is the first sighting,' said Mr Hodgson. 'It means Mother Nature is doing her job. You can't prove it on the basis of one fish species, but it is a good sign.' Event adjudicator Andy Cornish said that the humpback grouper was 'extremely rare in Hong Kong waters'. Information collected in the Big Fish Count will be used to build up the first computerised database mapping Hong Kong's fish biodiversity. Mr Hodgson said Sunday's event had been a huge success, particularly as the divers were restricted to searching for fish in a relatively limited area. Most of the diving took place to the north of the Ninepin Islands. The inaugural Big Fish Count was won by the University of Hong Kong diving team, which recorded 90 fish species. The award for the best fund-raising effort went to the Scubaworld team, while the 'fish of the day' award for sighting the humpback grouper went to the Pro-Dive team.