An estimated 10 metric tons of tilapia were lost in a fish kill that hit fish pens in Magat Dam, Isabela, according to the Bureau of Fisheries and Aquatic Resources.
BFAR said the fish kill was caused by a drop in the dam’s water level and low dissolved oxygen, which led to the death of tilapia in affected fish pens.
The municipalities of Ramon and Cordon were among the hardest hit, with fish pen operators reportedly losing more than ₱1 million due to the incident.
BFAR said it began receiving reports of the fish kill on Monday and advised fish pen operators to immediately harvest their stocks.
However, some operators failed to save their tilapia because the fish died suddenly. Authorities said dead fish usually sink first before later floating to the surface.
The Isabela Provincial Fishery Office said it is ready to provide assistance to affected fish pen owners to help them recover and resume operations.