Skip to content

Press Releases

Red tides sighted
Thursday, April 1, 2021

Two red tides have been sighted over the past week, an inter-departmental red tide working group reported today (April 1).

The first red tide was spotted by an oyster famer on March 26 at Deep Bay. The second red tide was spotted by staff of the Environmental Protection Department on March 29 at Chung Hom Kok Beach, Hong Kong Island.

The red tide at Deep Bay still persists while the other case at Chung Hom Kok Beach has dissipated. No fish deaths associated with the two red tides have been reported as at today.

A spokesman for the working group said, "The red tide at Deep Bay was formed by Takayama tuberculata, which is not common in Hong Kong waters, while the red tide at Chung Hom Kok Beach was formed by Noctiluca scintillans, which is common in Hong Kong waters. Both algae are non-toxic."

The Agriculture, Fisheries and Conservation Department (AFCD) urged mariculturists at the fish culture zones of Lo Tik Wan, Sok Kwu Wan and Po Toi, and related oyster farmers at Deep Bay 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.