Death of Dagupan ‘bangus’ in ponds blamed on tide

DAGUPAN CITY—Hundreds of “bangus” (milkfish) floated in ponds and cages in Barangay Salapingao here over the weekend, but many fish growers harvested their stocks before the fishkill, which was traced to a phenomenon called “neap tide” involving low oxygen levels in the water.

Hundreds more bangus swam close to the water surface to take in oxygen and were were quickly harvested, said city agriculturist Emma Molina.

A neap tide happens twice a month when gravitational forces of sun and moon cancel each other out, generating the lowest rise and fall of the tidal levels. Because the tides are at their lowest ebb, the dissolved oxygen in the water are also at their lowest levels.

Molina said the neap tide was recorded on Sept. 17 and 18. In the last two days, at least 100 tons of bangus from growers who harvested their stocks right were traded at the Magsaysay fish market here.

The average volume of fish traded at the market daily is about 5 tons, most of them coming from the ponds and cages in the towns of Anda, Bolinao and Sual.

The oversupply of bangus pulled down their prices by P20 a kilogram. On Monday, the wholesale price of bangus dropped to P80 a kilogram, from P105 to P115. Gabriel Cardinoza, Inquirer Northern Luzon