Several red tides have been sighted in Hong Kong waters over the past week, an inter-departmental red tide working group reported today (April 21).
Red tides at Silverstrand Beach and Clear Water Bay First Beach in Sai Kung; Stanley Main Beach, Turtle Cove Beach, Deep Water Bay Beach and Repulse Bay Beach on Hong Kong Island; and Cafeteria New Beach and Golden Beach in Tuen Mun were sighted by staff of the Leisure and Cultural Services Department from April 16 to 21. Another red tide was observed by members of the public at Sheung Sze Wan, Sai Kung on April 18.
The red tide at Silverstrand Beach has dissipated while the others still persist. No associated death of fish has been reported in these occurrences so far.
"The red tides at Cafeteria New Beach and Golden Beach were formed by Thalassiosira tealata, while the others were formed by Gonyaulax polygramma. Both are non-toxic and commonly found in Hong Kong waters," a spokesman for the working group said.
The Agriculture, Fisheries and Conservation Department (AFCD) urged mariculturists at Ma Nam Wat, Kau Sai, Kai Lung Wan, Tai Tau Chau, Leung Shuen Wan, Tiu Cham Wan, Tung Lung Chau, Po Toi O, Lo Tik Wan, Sok Kwu Wan, Po Toi, Ma Wan and Cheung Sha Wan fish culture zones to monitor the situation closely and increase aeration where necessary.
Red tide is a natural phenomenon. The AFCD's proactive phytoplankton monitoring programme will continue monitoring red tide occurrences to minimise the impact on the mariculture industry and the public.