More red tide alerts seen due to El Niño

Sonia Francisco is relieved. Now, she can gather and sell shellfish again after the red tide alert that was imposed in November last year on her hometown in Altavas, along with the towns of Balete and New Washington in Aklan province, was lifted on Jan. 29.

The feeling may just be short-lived, however. Fishing families and those living in the coastal areas should brace for more possible red tide alerts due to the prolonged dry spell, according to University of the Philippines marine scientist Rhodora Azanza.

“In line with the predicted strong El Niño event in the coming months, the intensity, number and duration of Pyrodinium blooms during this event can also be expected to rise,” Azanza, a professor of marine science at UP Marine Science Institute, said in an e-mail to the Inquirer.

Pyrodinium bahamense is the primary organism responsible for paralytic shellfish poisoning (commonly referred to as red tide) in the Philippines. The organism produces “cysts,” or seeds, that can be dormant for a period of time and deposited in the waters and sediments of the affected areas.

Its rapid increase or accumulation (bloom) is usually episodic and predictable, occurring during the southwest monsoon (amihan), Azanza said.

Major blooms were also recorded during the El Niño in 1997 to 1998. An increasing number of blooms were observed in 2015, from a single affected area in January to 15 areas in December, Azanza said.

The “harmful algal bloom” red tide phenomenon occurs when algae rapidly multiplies, producing toxins that can be fatal to humans and other wildlife. Higher than usual temperature of surface water brought about by global warming due to high carbon emissions is among the contributors to the occurrence of the blooms.

The shellfish toxicity level in the affected areas is above the regulatory limit of 60 microgram saxitoxin/100 grams of shellfish meat.

Fish in areas affected by red tide can be consumed but must be fresh and washed thoroughly. The internal organs, including gills and intestines, should be removed before cooking and eating, according to the Bureau of Fisheries and Aquatic Resources.

The harvesting and selling of shellfish are banned in the areas covered by the alerts, severely affecting the livelihood of residents in coastal communities.

Before the ban in Altavas was lifted, Francisco’s family struggled to recover from joblessness. “We are still waiting for assistance from the government because many of us were unable to harvest and sell oysters and other shellfish because of the ban,” she told the Inquirer in Hiligaynon.

She said at least 100 residents of her village of Odiong alone were severely affected by the ban. Those gathering oysters, who usually earned from P150 to P200 per day, had to sell roasted bananas so they could buy rice for their families.

The Aklan provincial board earlier declared a state of calamity covering Altavas, Batan and New Washington to enable the release of assistance to the affected residents.

Capiz, dubbed the country’s seafood capital because of its supply of fish, shellfish and other seafood, has also been reeling from red tide since last year.

Francisco said several residents had received 10 kilos of rice, eight packs of noodles and six cans of sardines per family. She was not among the beneficiaries because she has fish corrals or traps.