Fishery officials fear another fish kill

RAMON, Isabela — Fishery and irrigation officials here have sought the immediate suspension on the operation of fish cages at the Magat Dam reservoir here, fearing that such measures would be necessary to prevent the occurrence of another fish kill in the region.

Dr. Jovita Ayson, regional director of the Bureau of Fisheries and Aquatic Resources (BFAR), yesterday said the proposed moratorium came after hundreds of fisher folk have suffered heavy losses due to fish kill in the dam’s reservoir earlier this month, affecting more than 90 metric tons of tilapia worth some P5 million.

The incident, BFAR officials said, had affected hundreds of fisher folk who have fish cages installed at the dam’s reservoir located in various sites in Isabela, Nueva Vizcaya and Ifugao.

Ayson said the National Irrigation Administration (NIA) here wanted to start the moratorium "as soon as possible" to prevent another fish kill to occur. She said this would last until July this year, or until the dam regains its normal water elevation at 198 meters.

The Magat Dam, one of the biggest in Asia, was at its lowest water level (158 meters) when the fish kill occurred. NIA officials here said the elevation may even reach to as low as 147 meters when the dam’s water reserves would be released for irrigation.

Fish cage operators, Ayson said, would be greatly affected by the continuous lowering of the dam’s water level since the water depth where their cages are located is only about 12-20 meters.

Based on water analysis conducted by BFAR, according to Ayson, "dissolved oxygen in the reservoir has reached critical level." She said their office has already advised fisher folk to harvest all the remaining freshwater products there before another fish kill takes place. The Magat dam reservoir, largest in Cagayan Valley, is the biggest contributor to freshwater fishery production in Northern Luzon. Of the more than 4,500-hectare reservoir, only 450 hectares would be allowed for fish cage operation.

At present, 10,673 units of fish cages located in Isabela, Nueva Vizcaya and Ifugao were constructed at the dam’s reservoir, covering more than 600,000 square meters.

Constructed during the early 1970s, the mammoth Magat Dam cum hydro-power project, one of the biggest in Asia, has been providing irrigation waters to at least 85,000 hectares of farmlands in Cagayan and Isabela and some parts of Quirino and Ifugao.