Three red tides have been sighted in Hong Kong waters over the past week, an inter-departmental red tide working group reported today (April 13).
Two of the red tides were spotted by staff of the Agriculture, Fisheries and Conservation Department (AFCD) on April 10 at Hoi Ha Wan in Sai Kung and at Tung Ping Chau, while the other one was sighted by staff of the Marine Department on April 11 at Tai Tam Harbour, Hong Kong Island.
The red tide at Hoi Ha Wan in Sai Kung still persists while the others have dissipated. No associated death of fish has been reported.
A spokesman for the working group said, "All of the red tides were formed by Gonyaulax polygramma, which is non-toxic and commonly found in Hong Kong waters."
The AFCD urged mariculturists at Wong Wan, Ap Chau, Kat O, O Pui Tong, Sai Lau Kong, Tap Mun, Kau Lau Wan, Sham Wan, Lo Tik Wan, Sok Kwu Wan and Po Toi 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.