Population of invasive starfish species increasing in Samal

DAVAO CITY (MindaNews/14 September) — A species of starfish called crown of thorns is growing in number off the coast of Samal Island in Davao del Norte prompting the Bureau of Fisheries and Aquatic Resources (BFAR) 11 to start collecting them to prevent further damage to the coral reefs.

Speaking in Monday’s Kapehan sa Dabaw at SM City Davao, BFAR 11 director Fatma Idris said it has integrated the collection of the crown of thorns to their coastal cleanup activities in a bid to control its population.

She said the agency has yet to assess if the starfish have already caused some damage to the corals in the Davao Gulf, although their number was observed to have increased when it checked the diving sites in Samal.

She said they collected some 20 sacks of the species during their recent coastal cleanup off Pearl Farm Beach Resort in Kaputian in Samal.

The starfish were then buried near the resort, she added.

Idris said divers are careful not to break the starfish when collecting them as the severed parts can regenerate on their own, citing this is one of the reasons why their population is fast growing.

City Councilor Leonardo Avila III, environment committee chair of the city council, explained the exponential growth of these starfish can be attributed to lack of natural predators like the Napoleon wrasse, also known as the Humphead Wrasse, an enormous coral reef fish that grows over six feet long with a prominent buldge on its forehead and classified by the World Wildlife Fund as an endangered species.

Another nearly extinct natural predator of the invasive starfish are the trumpet shells, known to locals as “budyong”.

BFAR 11 has already banned the catching, consumption and selling of budyong shells for ornamental use, according to Idris.

She said they have already informed the vendors, most especially those at the Aldevinco Shopping Center that the selling of trumpet shells is prohibited, this being classified as an endangered species.

“Those who would try to take them outside of the city need to know that airport authorities will also confiscate them,” she added.

Avila added the coastal ecosystem needs balance but the population of crown of thorns and the lack of its natural predators has caused in imbalance that would endanger other sea creatures, most especially the corals where some of pelagic fish lay their eggs and the small ones take shelter.

The crown of thorns, which can grow about to 25-35 centimeters, prey on corals and absorb all their nutrients.

Corals take at least 50 years to recover, Idris said, citing this is why they have to control the population of the crown of thorns to prevent it from damaging the corals not only in Samal but also in other parts of the gulf.

Avila added humans also cause damage to the corals by throwing wastes into the sea.

“The destroyer is really the pollution. At least 80 to 90 percent of the pollution is the landwaste, 80 percent of which goes to the coral reefs,” he said, noting that the estimated volume of garbage dumped at sea is from 5 to 10 billions tons a year globally.

He encouraged Dabawenyos to participate in the International Coastal Cleanup, the biggest movement aimed at saving the marine natural resources, slated on September 19, 2015. All cities and municipalities in the region will participate in the event. (Antonio L. Colina IV/MindaNews)