The Star
Thousands of fish dead in Penang
By LO TERN CHERN | 30 Aug 2023

GEORGE TOWN: Thousands of fish were found dead along the shore in Teluk Bahang, believed to be due to the recent bloom of pink algae.

Universiti Sains Malaysia (USM) Centre for Marine and Coastal Studies (CEMACS) director Prof Datuk Dr Aileen Tan said while the algae was not known to have any direct toxicity or toxic effects, it was possible that the fish died due to high levels of discharge by the plankton.

“I understand that there was a smelly stench in the mud; that was why the bottom dwellers were affected first,” she said.

Tan said the phenomenon, considered a red tide bloom, had occurred in April during the hot spell with some amount of rain having brought nutrients from the land to the ocean.

“It is more intense this time compared to April because it happened during neap tide (compared to spring tide in April).

“The blooms were not drifted or carried away by the tides or waves this time,” she said.

Tan said several fish that were washed ashore and retrieved by the centre were found to be in a state of asphyxiation with their mouths wide open.

“We found them deprived of oxygen, resulting in unconsciousness or death due to suffocation.”

On Saturday, beachgoers and fishermen in Teluk Bahang were taken aback when they discovered thousands of dead fish along the shore.

A homestay operator who wished to be known only as Atan, 65, said about 20kg of fish were found dead in his pond before he found more lying lifelessly along the shore.

“At first, I thought the water in my pond was contaminated, but a fisherman later told me that thousands of dead fish had been floating in the sea nearby.

“This is the first time that such an incident has occurred in my 20 years of operating the business here,” he said.

On the same day, Cemacs deputy director Dr Annette Jaya Ram spotted the pink tide in Teluk Bahang, believed to be the algae bloom.

The Star also published aerial photos in April showing these widespread, thick streaks of garish pink algal blooms encroaching on the sea around Penang.

Scientists confirmed that it was non-toxic and not a threat to marine life beyond being an irritant. They also confirmed that the algae is Noctiluca scintillans. It is not toxic to humans and fish caught near Penang are still safe to eat.