Red tides sighted
Friday, January 29, 2021
Six red tides have been sighted over the past week, an inter-departmental red tide working group reported today (January 29).
A member of the public and staff of the Marine Department spotted the first and second red tide on January 23 at Long Harbour and Rambler Channel near Hoi Hing Road respectively. On January 26, members of the public spotted the third and fifth red tide at Lo Tik Wan, Lamma Island and Wu Kai Sha respectively, while staff of Environmental Protection Department spotted the fourth red tide at Cheung Chau Tung Wan Beach. The sixth red tide was spotted by mariculturist on January 28 at Shuen Wan Typhoon Shelter.
Apart from the first and fourth red tides, which still persist, the other four red tides dissipated. No fish deaths associated with the six red tides have been reported as at today.
A spokesman for the working group said, "The second to the fifth red tides were formed by Noctiluca scintillans, which is commonly found in Hong Kong waters and non-toxic. The first and sixth red tide were formed by Phaeocystis globosa and non-toxic Akashiwo sanguinea respectively, which are commonly found in Hong Kong waters as well. According to overseas literature, Phaeocystis globosa can produce foam that may cause harmful effects to fish."
The Agriculture, Fisheries and Conservation Department (AFCD) urged mariculturists at Tap Mun, Kau Lau Wan, Sham Wan, Wong Wan, Ap Chau, Kat O, O Pui Tong, Sai Lau Kong, Sha Tau Kok, Ma Wan, Lo Tik Wan, Sok Kwu Wan, Cheung Sha Wan, Yim Tin Tsai, Yim Tin Tsai (East), Yung Shue Au and Lo Fu Wat 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 to monitor red tide occurrences to minimise the impact on the mariculture industry and the public.