Philippines coral reefs face new El Nino threat

Ellalyn B. De Vera, Manila Bulletin 11 Mar 10;

An international conservation group warned Thursday that the current El Niño episode may have adverse effects on the recovering corals reefs in the country.

Gregg Yan, information, education and communications officer of the World Wide Fund for Nature Philippines (WWF-Philippines), noted that during the 1997-1998 El Niño event, Apo Reef in Occidental Mindoro suffered heavily from increased sea surface temperatures.

“These coral reefs damaged by bleaching are still recovering, particularly in Apo Reef,” Yan said in an interview.

“It is possible that the bleaching of corals could be repeated because of the current El Niño episode, but this would not be as strong as the impact of the 1997-1998 El Niño. However, the present phenomenon will affect the recovery of the corals that were damaged during the El Niño that happened more than 10 years ago,” he clarified.

Earlier reports showed that the 1997-1998 El Niño caused a decrease in the live coral cover nationwide by about 49 percent due to the coral bleaching event associated with the warming of sea water surface.

Yan explained that the localized rise in oceanic temperatures have a detrimental effect on corals, most of which rely on symbiotic algae, a single-celled organism, living within their tissues that help augment their feeding mechanisms and other processes for their survival.

“This (symbiotic algae) is what gives corals their ‘color’ because save for certain species like organ pipe coral, blue coral, sun coral and some others, most corals are white,” Yan said.

“When water temperatures rise, most corals react by expelling their symbiotic algae—in effect, bleaching themselves,” he added.

He said most "bleached" coral species could survive from several weeks to months, depending on the availability of plankton as their food.

However, with the lack or absence of their nutrients and symbiotes (food), corals eventually wither or die.

“Once this happens, algae can grow on the dead coral skeletons, choking off entire coral heads,” Yan pointed out.

He said a single square kilometer of healthy coral reef can produce approximately 30 to 40 metric tons of seafood annually.

“When the majority of corals die out, this dwindles to 10, five, or three tons, sometimes even less. Again, El Niño can rob us of food and livelihood,” he said.

Based on the 2002 Reefs at Risk in Southeast Asia (RRSEA) report published by the World Resources Institute (WRI), it estimated that the sustainable value of Southeast Asia’s coral reef fisheries is estimated at US$2.4 billion annually.

The Philippines has a total economic value from coral reef fisheries estimated at US$1.1 billion annually. The country ranks second in the region following Indonesia with US$1.6 billion annually.

The report also noted that Indonesia and the Philippines are among the world's largest archipelagos containing 77 percent of the region's coral reefs and nearly 80 percent of all the threatened reefs.

However, the 1997-1998 El Niño episode triggered the largest worldwide coral bleaching occurrence in history.

In Southeast Asia, an estimated 18 percent of the region's coral reefs were damaged or destroyed.

The remaining coral reefs in El Nido in Palawan were down to 5 to 10 percent due to the coral bleaching even in 1997-1998.

Yan explained that colder water surface carries with it nutrients from the depths of the ocean causes a “jump-start” of natural oceanic processes.

“When the warm water shifts to the west, colder water takes its place, re-channeling nutrients in a natural process called ‘upwelling.’”

“But this stops with El Niño — when the shift of warm to cold water weakens immensely. No nutrients means no food for our food - and no income for anyone,” Yan said.

The 27,469-hectare Apo Reef was one of the network of corals that was severely damaged by the El Niño phenomenon in 1998 due to raised ocean temperatures.

In 2007, fishing ban was implemented around Apo Reef, the largest coral reef in the Philippines and the second largest contiguous reef in the world after the Great Barrier Reef.

“WWF has been spearheading initiatives to help local communities adapt to a changing climate. To prepare the residents of Sablayan, Occidental Mindoro for sea level rise, oceanic acidification, salt water intrusion, coral bleaching and other climate effects,” Yan said.

WWF has partnered with Cebu Pacific for the “Bright Skies for Every Juan” program where passengers who book CEB tickets online will be given the option to donate to the WWF-led Mindoro climate adaptation project.