December 23, 2010

Hong Kong Corals Stable


Submitted by the Agriculture, Fisheries and Conservation Department

The results of Hong Kong Reef Check 2010 showed that local corals are generally in a healthy and stable condition, and exhibit a rich diversity of species.

In collaboration with the Reef Check Foundation, the Agriculture, Fisheries and Conservation Department (AFCD) has coordinated an annual survey of Hong Kong’s corals since 2000. The number of participants reached a record high this year, with 528 volunteer divers in 44 Reef Check teams from different sectors, including education institutes, green groups, commercial sectors, government departments and diving groups.

The Chairman of the Marine Parks Committee, Professor Paul Lam Kwan-sing, commended the participating teams for their zealous support and contribution to the success of Hong Kong Reef Check 2010, and presented them with souvenirs at an award presentation ceremony held December 4.

The three month survey, which started on June 3, covered extensive marine areas, including 33 sites of ecological importance in the eastern part of Hong Kong waters extending from Tung Ping Chau in the north to Ninepin Groups in the south, and including three marine parks – Hoi Ha Wan, Yan Chau Tong and Tung Ping Chau.

\"\"The survey results are encouraging. In general, the growth of corals in Hong Kong is stable and healthy. Indicator species are abundant in most of the survey sites. A variation in coral coverage (ranging from 30% to 78.1%) was recorded among 33 survey sites. Twenty-one of them, including dive sites within the marine parks, recorded a high coral coverage (above 50%). Among all sites, the public pier, Coral Beach at Hoi Ha Wan Marine Park and Sharp Island North recorded the highest coral coverage (ranging from 73% to 78.1%).

Most of the survey sites boast high species diversity. Of the 20 assigned indicator species, 19 were recorded, which is the same as last year. Wrasses, groupers, butterfly fish, sea urchins, sea cucumbers and cowries were species commonly found in the survey sites.

The Coral Watch bleaching monitoring system has been included in the Reef Check surveys since 2005 to enhance the monitoring of coral health status. By measuring the color intensity of the coral using a specially designed chart, the health condition of corals can be determined.

Corals at 11 sites were assessed using Coral Watch this year. The average health index was 4.54 (ranging from 3.71 to 5.69). The results were similar to last year’s (4.31). The average health index is well above the general average value (3), indicating the 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.

Corals form a highly productive system that supports various marine organisms by providing food and shelter. The AFCD will continue to organize Reef Check activities to collect important information necessary for devising conservation and management measures to protect the precious corals. For more information, please see AFCD’s Reef Check website.