Sulfur upwelling causes fish kill in Talisay, Batangas

A lake in Talisay, Batangas teemed with dead fishes after the occurrence of a phenomenon called sulfur upwelling.

According to Oscar Oida's report in GMA's "24 Oras" on Wednesday, some locals witnessed how the color of the waters suddenly changed.

"Para siyang mala-gatas na kulay... tapos amoy sulfur talaga," Maricar Loonstra, a resort owner said.

A few moments later, the dying fishes surfaced on the lake, most of which were small Bangus and Tilapia.

Some residents even tried to gather the dead fishes.

The Bureau of Fisheries and Aquatic Resources (BFAR), however, warned that these shall not be eaten to avoid harm.

The fisherfolks tending fish cages in Talisay estimated that the cost of damage amounts to millions of pesos.

BFAR explained that during a sulfur upwelling, the sulfide level in the water rises while the amount of oxygen dwindles.

This occurs when strong winds, usually from November to February, cause big undercurrents which stir the underwater sediments.

The lake's color has already returned to normal on Tuesday and fish vendors in the town said that the incident did not affect their business. —Dona Magsino/ LDF, GMA News