CoTS Control


Aimed at mitigating the impact of a current outbreak of COTS in the Beqa Lagoon area, and provide the tools for long-term adaptive management allowing future control of COTS populations.

[Villagers quantifying and measuring the collected CoTS]

Crown-of-thorns starfish (COTS) are marine invertebrates, reaching up to 80 cm in diameter, feeding primarily on hard corals. They occur naturally on reefs throughout the Indo-Pacific region. The continuing overexploitation of their natural predators, such as the giant triton snail, the titan triggerfish and the humphead Maori wrasse; alongside eutrophication of otherwise nutrient-poor tropical waters, creating favourable conditions for COTS survivorship, leads to population outbreaks. The widespread impact of COTS has been increasing in recent decades, becoming one of the leading causes of coral cover losses in South Pacific coral reefs.

Efforts are focused on manual removals by consolidated task forces composed by local community members, educated on their impact and trained at locating them. An emphasis is on creating education, awareness and management strategies to mitigate the impact of overexploitation of COTS natural predators, and of watershed management, reducing the outflow of nutrients to the reef from piggeries situated either adjacent to beaches.