Massive Fish Kill Hits Pangasinan Town, Climate Change and Pollution Suspected

BINMALEY, PANGASINAN, Philippines — Instead of bringing their harvest to market, fish farmers in this town spent the past two days burying tons of dead “bangus” (milkfish) in freshly dug pits after a massive fish kill wiped out stocks in several villages. “The fish mortality was widespread. Almost all of the cultured fish died during the wee hours, when dissolved oxygen levels in the ponds dropped,” said fishery technician Joey de Leon. He said the fish gasped for air and eventually died when dissolved oxygen levels became critically low, especially in ponds without aerators or other intervention. De Leon estimated that fish farmers lost “perhaps half a million fish of different sizes” in the villages of Caloocan Norte, Buenlag and Salapingao. The operator he works for alone lost 40,000 bangus fingerlings worth about P280,000, with each fingerling valued at P7. Lune Quinto, who operates a one-hectare fishpond in Barangay Gayaman, said she and her husband managed to save most of their 17,000 bangus by running aerators continuously for the past two weeks. “We lost only around 1,500 fish weighing about 200 to 250 grams each, but we spent a lot on gasoline just to keep the aerators running,” Quinto said. Their neighbor, however, was less fortunate, losing 2,000 market-ready bangus during the fish kill. “He had aerators, but they perhaps could not produce enough dissolved oxygen for the bigger fish, which weighed around 600 to 700 grams each,” she said. The fish kill also affected other species. “Sari-sari” (different species) of fish, including the hardy black chin “tilapia” (molmol), an invasive species regarded as a pest by many aquaculture operators, were found floating dead in rivers on July 9 and July 10. Fish farmer Rico Aquino said about 80 percent of the “malaga” (siganid) he was raising in ponds along the Caloocan Sur River also died. “I lost 12,000 fingerlings and 10,000 grow-out fish that I was supposed to harvest in the next few days,” Aquino told the Inquirer. “I estimate my losses at half a million pesos.” Aquino said he tried to salvage his stocks as soon as water quality in the river deteriorated but managed to recover only about 20 percent by using fishing nets. He explained that malaga stay near the bottom of the water column, making it necessary to drain ponds before the fish can be collected. Fish farmers blamed the erratic weather associated with climate change for triggering the fish kill. “The sun is shining, then it suddenly rains. The temperature rises again, then another rain comes,” De Leon said. He added, however, that poor aquaculture practices may have aggravated the problem. “Some operators overfeed their fish. The excess feed settles at the bottom of the ponds, decomposes and pollutes the water,” Aquino said. Aquino said Binmaley’s rivers have also become increasingly polluted because they draw water from nearby Dagupan City, where a large aquaculture industry operates. De Leon said fish farms in Dagupan’s Salapingao area were likewise affected, although city authorities had yet to issue an official report. He also noted that Binmaley’s rivers were once replenished by waterways from Lingayen, but the construction of the Lingayen-Binmaley-Dagupan bypass road blocked several natural channels. Fish farmers appealed to the Bureau of Fisheries and Aquatic Resources (BFAR) for assistance as they struggle to recover from successive disasters, including recent typhoons and flooding. BFAR regional director Remely Lachica said the provincial fisheries offices and laboratory personnel remain ready to assist fish farmers. /cb Information Source: Inquirer NewsInfo