Bleaching brought by El Niño threatens PH coral reefs – expert

MANILA, Philippines — Coral reefs around the world are under threat from another round of bleaching as ocean surface temperature is expected to rise in the latter part of the year, according to a leading marine scientist.

According to Professor Terry Hughes, Australia’s foremost marine biologist on coral ecosystems, massive coral bleaching is “entirely likely” in some reef areas including Southeast Asia due to the El Niño phenomenon, which is forecast to occur in the latter part of 2012.

Hughes said the weather bureau in Australia has seen a “50-50” chance of El Niño, a weather pattern that results in dry spells, in 2012.

“If we get severe El Niño, there would be more bleaching, that is the expectation,” he said in an interview.

Hughes, a convenor of the 12th International Coral Reef symposium to be held in July in Australia, was in Manila and Dumaguete last week to talk about the Coral Triangle Initiative and meet with local marine biologists.

Hughes noted that climate change has been one of the main causes of stress on coral reefs, although some species might be more prone to bleaching than others.

Coral bleaching happens when zooxanthellae, the protozoa that gives it coloration, dies—an indicator that the reef is under stress or dying. A change in temperature is often the main cause of bleaching.

Even after the cause of the stress ends, bleaching still tends to continue, which makes the recovery of corals a hard and long process, according to scientists. The last time the Philippines had massive bleaching was reported in 2010, an El Niño year.

Aside from climate change, overfishing and land runoff were also seen as major threats to the existence of coral reefs around the world.

Deforestation and mining activities have been leading to the runoff of chemicals and soil, which, in turn, has been contaminating fringe reefs on the coast, he said. Destructive fishing practices could also destroy coral reefs, he added.

Hughes stressed the necessity of protecting of coral reefs, particularly in the Coral Triangle. Preserving the biodiverse marine area is not just a boon to conservationists, but to ordinary citizens in countries surrounding the triangle.

The Coral Triangle, recognized as the global epicenter of marine biodiversity, refers to a roughly triangular area of the tropical marine waters of Indonesia, Malaysia, Papua New Guinea, Philippines, the Solomon Islands and Timor-Leste that contain at least 500 species of reef-building corals.

Hughes explained that the health of the Coral Triangle has been directly impacting on the lives and livelihoods of millions who have been depending on corals and marine resources for a living, including from fishing and tourism.

“The Philippines has very rich marine biodiversity that is intrinsically linked to all other marine ecosystems in the Pacific and elsewhere. They face grave threats right now and Filipino marine biology students have their work cut out for them even before they venture out of school,” said Hughes.

Hughes capped his first visit to the Philippines on World Oceans Day, June 8, with a lecture at the Silliman University, a “Scientists in Schools” initiative of the Australian Embassy in Manila. Australian Ambassador Bill Tweddell said that the science program has been supporting the Philippine priority of raising appreciation for science education and research as a path to sustainable development.