Dr Kongkiat, Chief of the Phuket Marine Biological Centre (PMBC), which is operated by the Department of Marine and Coastal Resources (DMCR), urged people to not collect or eat the red sea urchins, which have washed ashore in the many hundreds during the past two spring tides, most recently on Monday (Mar 15).
The sea urchins have risen to the surface close to shore at Patong Beach to feast on a bloom of macro algae in Patong Bay, Dr Kongkiat said.
“These algae are the food of the sea urchin. Algae thrive and are carried by the water currents, as well as sea urchins,” he explained.
“The phenomenon of sea urchins stranded on the beach is explained by the phenomena of these algae blooms, together with this period being the spring tide with high tides,” he added.
Dr Kongkiat urged people to not remove the sea urchins for the area
“We shouldn’t take these sea urchins out. We should help them into the sea to serve as the ‘Cleaner of the sea’,” he said, as the urchins will eat the macro algae.
Dr Kongkiat pointed out that the algae bloom was the result of higher concentrations of nutrients in the beach water.
“For algae to be able to bloom, it needs food like fertilizer we use to feed plants,” he said.
“These fertilizers do not come from just anywhere, but are elements of the wastewater that we release into the sea,” he said.
Phuket officials at all levels for more than a decade denied that wastewater being released into Patong Bay was a consistent contributing factor to algae blooms at Patong Beach.
However, Patong Municipality health officials in 2016 finally admitted that during the heavy influx of tourists during the pre-COVID tourism high season as much as 20% of Patong’s wastewater flowed untreated into the bay.
The rise in effluent being released into the bay consistently led to algae blooms, the health officials admitted.