''Red tide'' kills 1,500 tons of HK fish

By Tan Ee Lyn

HONG KONG (Reuters) - A massive algae bloom known as ``red tide'' has killed 1,500 tons of Hong Kong's farmed fish, a government official said Monday.

As environment workers battled to dispose of rotting fish, the government warned beachgoers to keep out of the water as the algae appeared off several popular beaches.

Joseph Sham, acting assistant director of fisheries at the Agriculture and Fisheries Department, told a news conference the algae type was gyrodinium and that the current red tide was the most serious he had seen.

``This is the most serious red tide I have known,'' Sham said.

Made up of microscopic organisms, the algae multiplies very quickly and turns swathes of sea a reddish brown.

``Red tide is a natural phenomenon. The causes are very complicated,'' Sham said without elaborating.

The Conservancy Association in Hong Kong earlier said it believed pollution was the main reason why red tide was becoming more frequent and more severe.

``We can see that as the waters get more and more polluted, the number of red tides are increasing,'' executive member Hung Wing-tat said on government radio.

The attack, which began in mid-March, has been fatal to fish because the algae disrupt their respiratory systems.

``It sticks to the gills of the fish, causing mucus, and the fish cannot breathe,'' said Sham.

All day, lifeguards stood by at beaches -- Shek O, Repulse Bay, Middle Bay, Chung Hom Kok and South Bay -- warning people of the danger as red warning flags were raised and a recorded loudspeaker message warned swimmers to keep out of the water.

``Traces of red tide have been found in this beach. Please leave the water,'' the message rang out through megaphones.