By Reef Check Hong Kong
In collaboration with Reef Check Hong Kong, the Agriculture, Fisheries and Conservation Department (AFCD) has coordinated an annual survey of Hong Kong's corals since 2000. AFCD held a presentation ceremony December 3 in appreciation of the work of Reef Check teams and their contribution to the success of Hong Kong Reef Check 2011.
The 41 Reef Check Teams comprised more than 500 divers from different sectors of the community, including education institutes, green groups, commercial sectors, government departments and diving groups.
The water areas surveyed are extensive, covering 33 sites of ecological importance. The three-month exercise starting in June covered coral sites in the eastern part of Hong Kong waters extending from Tung Ping Chau in the north to the Ninepin Group in the south, including three Marine Parks - Hoi Ha Wan, Yan Chau Tong and Tung Ping Chau.
The survey continues to yield encouraging results. In general, the growth of corals in Hong Kong is stable and healthy. Indicator species are abundant at most of the survey sites. A variation in coral
coverage (ranging from 20% to 77.5%) was recorded among 33 survey sites. Twenty-three sites, including dive-sites within the Marine Parks, recorded high coral coverage (above 50%). Among all sites, Bluff Island and Sharp Island North recorded the highest coral coverage of 77.5%.
Most of the survey sites boast high species diversity. Out of the 20 assigned indicator species, 19 were recorded - the same as last year. Wrasses, groupers, butterflyfish, sea urchins, sea cucumbers and cowries were species commonly found at the survey sites.
Coral Watch has been included in the Reef Check since 2005 to enhance the monitoring of coral health status. By measuring the colour intensity of the coral using a specially designed Coral Health Monitoring Chart, the health condition of corals can then be determined.
Corals at 11 sites were assessed using the Coral Watch tool. The average health index is 4.14 (ranging from 3.5 to 4.95 out of 6). The results are similar to last year (4.54). The average health index is well above the general average value (3), indicating corals were in healthy and stable condition.
Coral bleaching and some coral damage were observed at a few sites but the impact was minor and localized.
The results of "Our Coral Underwater Photo Contest 2011" were also announced at the ceremony, with 13 winners in total and three photos chosen for the top prizes. Jointly organized by Reef Check Hong Kong and AFCD, the aim of the contest was to enhance public understanding and interest in coral ecology and promote local underwater sites for coral appreciation. Over 160 entries were received. All winning photos are on display at www.afcd.gov.hk.
In addition, the AFCD introduced a new iPhone application, "Hong Kong Reef Check". Users can browse the coral coverage of 33 survey sites, and the distribution and photos of indicator species including reef-building corals, fish and invertebrates. Users may also make use of the Quick Response (QR) Code to download the application.
Corals form a highly productive system that supports various marine organisms by providing them food and shelter. The AFCD will continue to organise Reef Check activities to collect important information necessary for devising conservation and management measures to protect the precious corals.