“Coral reefs are a jeweled belt around the middle of the planet. A coral reef cannot be properly described. It must be seen to be thoroughly appreciated.”
—Sidney Hickson, British zoologist
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The Philippines consists of more than 7,100 islands, a significant number of which are bordered by fringing coral reefs. With a total reef area of approximately 25,000 square kilometers, it ranks as the third largest globally, and its waters are renowned for possessing the highest biodiversity of corals.
Overfishing, destructive fishing, and decades of pollution have taken a toll on the country’s coral reefs and have a negative impact. But in recent years, the biggest concern is climate change, a long-term change in the average weather patterns that have come to define Earth’s local, regional and global climates.
Coral reefs are among those that are greatly affected by climate change. A sudden or abrupt change in temperature is bad for corals. It leads to stress that causes coral bleaching, and eventually, death of corals.
“Bleaching is not a good thing,” Dr. Terry Hughes, a distinguished professor at James Cook University told us some years back when we attended the International Coral Reef Symposium in Cairns, Australia. “Thermal stress due to global warming is not good.”
According to Dr. Hughes, as global warming intensifies, coral bleaching would also increase at an unprecedented level. “Bleaching events are expected to increase in terms of frequency,” said Dr. Hughes, a fellow of the Australian Academy of Science.
On what bleaching of the corals is, John C. Ryan of the Washington, D.C.-based Worldwatch Institute, explains: “When subjected to extreme stress, (the corals) jettison the colorful algae they live in symbiosis with, exposing the white skeleton of dead coral beneath a single layer of clear living tissue. If the stress persists, the coral dies.”
Bleaching has been cited as “the worst threat to the survival of coral reefs.” “While its causes are not known, bleaching appears when ocean temperatures are abnormally high,” Ryan writes.
But the biggest threat still comes from deforestation. As the recent study published in Nature Communications puts it: “Curbing sediment pollution to coral reefs is one of the major recommendations to buy time for corals to survive ocean warming and bleaching events in the future. Our results clearly show that land use management is the most important policy action needed to prevent further damage and preserve the reef ecosystem.”
The researchers of the study found that mitigating erosion on land is more important to saving coral reefs right now than even addressing climate change. “Without addressing the current issues, we won’t have living coral reefs to try and save from warmer ocean temperatures,” they pointed out.
When trees are felled, the area they once shaded becomes uncovered. An uncovered area is vulnerable to erosion. Consequently, during rainfall, the soil is washed away and makes its way into rivers and streams. It is only a matter of time before the eroded soil – now transformed into sediment – reaches the open seas and blankets coral reefs.
Sediments can harm coral reefs in various ways. Firstly, they obstruct sunlight, which is essential for photosynthesis. Secondly, sediments can directly suffocate and wear down coral. Additionally, sediment can lead to an increase in macroalgae, which compete with corals for resources. Elevated levels of suspended sediment can also hinder coral recruitment.
More than 90 years ago, the Philippines was almost totally covered with forest resources distributed throughout the 30 million hectares. In the 1950s, only three-fourths of the archipelago was covered with forest, according to the Department of Environment and Natural Resources. By 1972, the figure had shrunk to half – and by 1988, only a quarter was wooded, and just one tiny fraction of this was virgin forest.
Logging – whether legal or illegal – is one of the primary culprits of the fast disappearance of the country’s forest resources.
“Logging is most ecologically destructive in the mountains,” wrote multi-awarded science journalist Alan Robles in an article circulated by the Philippine Center for Investigative Journalism (PCIJ). “It is next to impossible to replant trees on rocky mountain sides once their thin skin of topsoil has been washed away.”
Why should we be concerned about the vanishing coral reefs? Fish, like rice, is the staple food of Filipinos. An estimated 10%-15% of the total fisheries come from coral reefs. About 80-90 percent of the income of small island communities comes from fisheries. “Coral reef fish yields range from 20 to 25 metric tons per square kilometer per year for healthy reefs,” said the late Dr. Angel C. Alcala, a marine biologist.
“Despite considerable improvements in coral reef management, the country’s coral reefs remain under threat,” said Dr. Theresa Mundita S. Lim, former director of the Biodiversity Management Bureau of the Department of Environment and Natural Resources.
The Philippine government made and introduced many laws in an attempt to protect the natural environment on the islands and in the national territorial waters. But the government cannot do it alone; help from individuals is also needed to save the reefs from total annihilation.
“We are the stewards of our nation’s resources,” said Dr. Rafael D. Guerrero III, an academician with the National Academy of Science and Technology, “we should take care of our national heritage so that future generations can enjoy them. Let’s do our best to save our coral reefs. Our children’s children will thank us for the effort.”
