Cebu vlogger helps control crown-of-thorns starfish outbreak with coconut vinegar

A Cebu-based vlogger is helping control the spread of crown-of-thorns starfish (COTS) in Badian by injecting coconut vinegar into the coral-eating species.

According to Kuya Kim’s report on “24 Oras,” Tuesday, Bonifacio Jomio always carries a syringe filled with coconut vinegar or tuba whenever he dives in their coastal waters and injects the solution into the starfish to prevent them from destroying nearby coral reefs.

He encounters more than 50 COTS a day in the area, adding that the species has become a pest in Badian due to their growing numbers.

“Kapag outbreak po nila, posibleng mamamatay lahat po ng corals,” he said.

Per Kuya Kim, COTS, or Acanthaster planci, are large, spiny starfish that can have 10 to 21 arms covered in venomous spines containing saponins.

“Immediate effect nito is namamaga, nagkakaroon ng swelling ‘yung area kung saan natusok. Severe ‘yung pain na nararamdaman,” said Glennville Castrence, a faculty member at the College of Fisheries and Aquatic Sciences, Mindanao State University - General Santos. 

COTS are known corallivores, feeding directly on corals. While they play a role in maintaining coral biodiversity, a COTS outbreak can rapidly destroy coral reef systems. 

A single female COTS can release millions of eggs during spawning. Kuya Kim added that their natural predators, such as the giant triton snail, have become scarce.

“‘Pag may outbreak, mas madami ‘yung kinakain nila na mga corals kaysa nilalaki ng mga corals natin,” Castrence said.

Bonifacio also shared that he has already observed areas in Badian where corals are turning white, prompting him to act after seeing other content creators document similar control efforts. 

“Hindi po siya mamamatay agad-agad. Unti-unti po siyang mananamlay,” he said.

He added that many residents appreciate his initiative, with some even donating supplies for his control efforts.

“May mga studies din kasi na talagang nagpapatunay na very effective ’yung ating mga vinegar. Nakitaan kasi sa mga trials, hindi talaga sila nagko-cause ng harm sa other marine na mga organisms,” Castrence also said.

—Carby Rose Basina/CDC, GMA Integrated News