Starfish threatens RP coral reefs

A global conservation group reported yesterday a "massive outbreak" of coral-eating starfish in various parts of the country, as the temperature continues to rise and tourists flock to different beaches nationwide.

The World Wildlife Fund for Nature-Philippines (WWF) said that the rash of the coral-eating crown of thorns starfish has been detected in many Philippine reefs, including those in Mabini, Batangas; Apo Reef off the Dumaguete coast; Puerto Galera in Mindoro; Roxas in Palawan; Bolinao in Lingayen Gulf; and Kiamba and Glan in Sarangani Bay.

WWF believes it is possible that many other coastal areas have been affected by the outbreak of the crown of thorns starfish as well.

"As of today, the damage is not yet great," said WWF-Philippines media officer Gregg Yan. "(But) unless we act now, entire hectares of our local reefs will be decimated and eaten by summer’s end."

Yan explained that "a serious infestation" of the crown of thorns starfish (Ancanthaster planci) can destroy entire sections of coral reefs in weeks. He said that a single crown of thorns starfish can consume six meters of healthy reef annually.

As this developed, the Department of Environment and Natural Resources (DENR) said it has yet to receive complaints or reports about the invasion of crown of thorns starfish into the country’s reefs.

However, DENR Protected Areas and Wildlife Bureau (PAWB) director Dr. Mundita Lim said they would verify immediately the information from the agency’s field offices and links nationwide.

Lim also said they will mobilize divers to help remove the crown of thorns starfish from the affected reefs.

"Every now and then, there is really a surge of crown of thorns (starfish) but, in recent years, it has become more frequent," Lim told The STAR.

According to Lim, the invasion of the crown of thorns starfish occurs when there is disturbance on the marine ecosystem brought about by rising temperature or global warming, the El Niño phenomenon, or organic pollution.

She also said the growing population, which includes the influx of tourists or visitors, in coastal areas contributes to such invasions by the crown of thorns starfish.

At this point, the WWF appealed to the public to help alleviate the outbreak of crown of thorns starfish especially as the nation’s summer vacation kicks off with the observance of Holy Week.

Yan urged divers and those who snorkel to spot a crown of thorns starfish, which looks like a cross between a sea urchin and a large grey starfish.

Yan said it is highly possible that one will find the crown of thorns starfish near conspicuous portions of healthy coral heads that have been worn white.

However, WWF warned against touching the crown of thorns starfish with one’s bare hands and cautioned the public to "be extremely careful" in handling the starfish.

WWF president Lorenzo Tan said the long spines of the crown of thorns starfish can deliver severe stings and that bare-handed contact will almost surely inflict severe swelling, pain and nausea that can last from hours to days.

Tan said that the proper method of collecting and disposing of crown of thorns starfish is to pry them gently off the coral using tongs.

He also said the crown of thorns starfish should not be cut up, because its severed parts may regenerate. Tan added that all collected crown of thorns starfish should be placed in a bucket or a holding bin before "disposing them humanely on the beach." The starfish should be burned in an open space.

"We have to act now, and not when summer is over – and the damage has been done," Tan said. "Ultimately, the best response is to keep the reefs healthy: Stop overfishing, manage sewage and agricultural runoffs and promote balanced reef biodiversity."

WWF said that, each summer, when ocean temperatures and nutrient levels increase and give rise to algal blooms, many Philippine reefs experience crown of thorns starfish outbreaks.

Major predators that should, under normal conditions, keep the crown of thorns starfish populations in check have suffered from the intense pressures of population and fishing.

Among these predators are several wrasse species, including the Napoleon wrasse or mameng, the Giant Triton (Charonia tritonis) and the coral’s own polyps.

All of these predators are steadily declining due to illegal collection for food and the aquarium trade, the WWF said.

"Normally, reefs should be left alone to deal with unusual occurrences such as this," Yan said. "However, the situation facing the country’s reefs is far from normal."

According to the WWF, the Philippines once had 25,000 square kilometers of coral reef. A recent World Bank study revealed that barely one percent of the country’s reefs remain pristine, while over 50 percent of the country’s reefs are unhealthy.

In February, the WWF organized crown of thorns starfish cleanups at Apo Reef, where hundreds of the starfish were netted.

WWF observed that this year’s return of the coral-eating starfish is estimated to be "in even greater numbers." – with AP