Poisoning, not just thermal shock eyed on Davao Sur fish kill
Environment and fisheries officials do not rule out chemical poisoning as the cause of 1-ton fish kills last week in a barangay along Padada River in Davao del Sur even if water and fish sample analysis show thermal shock was the immediate cause.
Officials from the Bureau of Fisheries and Aquatic Resources and the DENR’s Environmental Management Board (EMB) released their report Monday showing the 1,000 kilograms assorted fish kill was caused by a sudden increase in water temperature.
The species include freshwater eels, goby, milkfish, tilapia, hito, shrimps, crablets, among others.
EMB revealed the fish kills occurred near a banana plantation area and the processing plant of the Davao Sugar Central Corporation (Dasureco), which maintains a concrete “spray pond” to contain hot water used to cool down the factory’s condenser and evaporator equipment.
Madeleine Lourdes Navarce, BFAR’s regional fish health officer, however, said the Fertilizers and Pesticides Authority needs to test the samples to see why fish samples showed signs of chemical toxicity.
Navarce said some dead fish samples taken from the site showed clogged and hemorrhagic gills, bulging eyes, although other organs appeared normal.
Fish samples had been submitted to the FPA, which is expected to release its report a week after, Navarce said.
The water temperature in the fish kill area was at 32 degrees Celsius when BFAR technicians measured it around 9a.m., a few hours after residents reported that dead fish were found in the vicinity.