Crown of Thorns Starfish
by Isaac Rounds

Divers clutch wooden spears as they plunge beneath the waves, hunting hordes of hungry starfish destroying the coral reefs around the Cook Islands. These makeshift tools are their best weapons in the war against crown-of-thorns starfish, a coral-munching species eating through tropical reefs already weakened by climate change.

The Cook Islands, a South Pacific nation of about 17,000 people, is in the grips of a years-long outbreak, says marine biologist Teina Rongo. "It can completely kill off the entire reef, right around the island," said Rongo, who organizes volunteers protecting the reefs fringing the isle of Rarotonga.

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