Results of Reef Check 2023 announced (with photos)
​The Agriculture, Fisheries and Conservation Department (AFCD) announced today (December 3) that the results of the Hong Kong Reef Check this year showed that local corals are generally in a healthy condition and that the species diversity remains on the high side.
The Hong Kong Reef Check 2023, a five-month programme started this June, covered a wide range of locations including a number of sites of ecological importance as well as the best coral sites known in the eastern part of Hong Kong waters, extending from Tung Ping Chau in the north to the Ninepin Group in the south. Among the 33 survey sites, nine were within marine parks, including Hoi Ha Wan Marine Park, Yan Chau Tong Marine Park and Tung Ping Chau Marine Park.
A variation in coral coverage, ranging from 12.8 per cent to 74.3 per cent, was recorded among the survey sites. Ten sites recorded over 50 per cent of coral coverage, including five sites within marine parks. Among all sites, A Ma Wan of Tung Ping Chau recorded the highest coral coverage of 74.3 per cent.
An AFCD spokesman said, “Coral bleaching was observed this summer at six survey sites, including Kai Kung Tau of Kat O, Au Yue Tsui of Yau Chau Tong, Wu Pai of Crescent Island, Coral Beach of Hoi Ha Wan and Siu Long Ke. The impact was minor and localised. It could be caused by the elevated water temperature in this summer.”
Voluntary dive teams of the Reef Check also assessed the condition of corals at 10 sites using the Coral Watch tool. By measuring the colour intensity of the coral using a specially designed Coral Health Monitoring Chart, the health condition of corals can be determined. The deeper the colour, the healthier the corals. The average health index of the sites was 4.28, which was slightly better than last year’s figure (4.06). The average health index is well above the general average value (3), indicating that the corals are generally in a healthy condition.
The survey method and data collection of the Hong Kong Reef Check’s follow international standards. Reef Check divers recorded coral coverage and health status as well as other indicator species (including 20 species of fish and invertebrates). All the 20 assigned indicator species were recorded in the survey sites, with butterfly fish, groupers, wrasses, snappers, sea cucumbers, sea urchins and cowries found in abundance. A majority of the survey sites were found to have a high species diversity. Most of the groupers, wrasses, sweetlips and snappers were found in survey sites at Town Island in eastern waters and at Port Island, Wong Chuk Kok Hoi and Crescent Island West in north-eastern waters.
No signs of destructive fishing practices were observed at any sites. Abandoned nets were found at eight sites but their impact was minor. The AFCD will arrange for a contractor to remove them.
The Hong Kong Reef Check is part of a global programme to promote the sustainable management of coral reefs. The Hong Kong Reef Check aims to raise public awareness of the ecological importance of corals and the need for coral conservation, and to provide updated information on local corals for conservation and management. The Hong Kong Reef Check Foundation held the first Reef Check in 1997. The AFCD has collaborated with the Foundation in conducting the survey since 2000, with growing attention and support from the public. This year, 103 dive teams involving over 1150 volunteer divers took part in the exercise, representing about 30-fold the number in 1997. The AFCD awarded souvenirs and certificates during the Closing Ceremony held today to the Reef Check teams and participating scientists to recognise their contribution.
Coral reefs are highly productive systems, which support a high diversity of marine life. The AFCD has been dedicated to implement a series of measures and programmes for conservation of coral in Hong Kong. Key measures include designation of marine parks and marine reserves, organisation of a range of education and publicity activities to enhance public understanding of the importance of coral communities, a yearly Reef Check to monitor the status of coral communities of Hong Kong, and studies and mitigation measures to restore degraded coral communities, etc.
