KORONADAL CITY—Heavy rains due to the southwest monsoon, or “habagat,” triggered a fish kill in Lake Sebu, South Cotabato, affecting tilapia farms that are the main source of fish for many localities in the province.

Jose Rudy Muyco, lake warden of Lake Sebu town, noted that just like in the past, a fish kill, locally known as “kamahong,” follows episodes of torrential rains similar to the ones experienced in Mindanao several days ago.

“The rainwater that flowed from the forest to the lake could be contaminated, and it affects the oxygen level of the lake,” Muyco said, adding that other factors could have contributed to the kamahong, like “overpopulation” of fish stock.