By Apinya Wipatayotin, 17th March 2016;
A plankton bloom is thought to be one of the causes behind the mass of dead fish that has washed up on Ta Kuan beach in Rayong, authorities said yesterday.
Supawat Kanadireklarp, director of state agency Eastern Marine and Coastal Resources, led officials yesterday to the beach near the Map Ta Phut industrial estate to collect plankton and sea water samples for testing.
“We will take around one week to complete our laboratory tests to determine whether a plankton bloom is one of the causes of the thousands of dead fish found washed up on this beach. It might have been caused by other factors as well,” said Mr Supawat.
Fishermen on Tuesday reported to local authorities that the dead fish had washed ashore along the beach and told them they still didn’t know the real cause of the death of so many fish.
They first found the dead fish on Monday.
Some fishermen said it was a normal occurrence every year, though this year many more appear to have died than last.
Most of the dead fish were identified as Rabbitfish (Siganus sp.), locally known as pla salit hin.
It is the fifth year in a row the fishermen say they have witnessed mass fish deaths.
Mr Supawat cited plankton bloom as one of the likely causes because the natural phenomenon can deprive the environment of oxygen which the plankton consumes for reproduction.
Meanwhile, a senior official from the 13th Regional Environment Office based in Chon Buri said an initial examination found dissolved oxygen and pH levels were normal.
Authorities need to conduct further tests to determine the cause.
They also collected water samples to check for heavy metals and other toxic materials that could lead to such a large amount of dead fish, a senior official said.
Penchome Sae-Tang, director of Ecological Alert and Recovery Thailand, said it was hard to believe that a plankton bloom was to blame.
Ms Penchome said water from the Chak Mak canal that leads from the industrial estate to the sea was an unusual dark colour.
She said her team will collect water samples from the canal to help determine whether the water is polluted and if it is linked to the deaths of marine life.
However, an initial inspection of water in the canal found it was normal.
Officials will conduct further tests, Map Ta Phut Industrial Port chief Chamrus Nenthong said yesterday.
It is too soon to conclude the fish died due to poisoning from waste water, he said.