Bruce Butterworth, left, and Jonas Furberg at Blue Planet Scuba, the dive shop Furberg operates on S Street NW in Washington. (John Kelly/The Washington Post)

Dupont Circle is a long way from the tropical islands of Indonesia, but a dive shop at 18th and S streets NW called Blue Planet Scuba has become the mustering point for an international effort to combat a coral-eating monster.

“They’re nasty little buggers,” Bruce Butterworth said of the crown-of-thorns starfish, or COT.

The COT — scientific name: Acanthaster planci — is not a cute little starfish. It’s more H.R. Giger than Walt Disney.

“Think of the Blob, with multiple tentacles,” said Butterworth, a transportation security consultant who lives in Springfield, Va.

Multi-limbed and covered in venomous spikes, a COT can grow as big around as a trash-can lid. Armies of them munch their way through coral.

Butterworth, 68, has been venturing underwater since the 1980s, first snorkeling and then certifying as a scuba diver. In that time, he’s witnessed the slow decline of the world’s coral reefs.

“Global warming, plus other stresses and damage from people, has been creating problems,” he said. Two years ago on a trip to Grand Cayman in the Caribbean, he learned that a leading coral expert happened to be nearby.

That was Phil Dustan, a professor at the College of Charleston. Butterworth asked Dustan where he could see coral — and what he could do to help save it.

Dustan pointed him toward a remote Indonesian archipelago called Raja Ampat in a patch of ocean called the Coral Triangle. Dive there, Dustan said, to see thousands of different types of coral, along with the many creatures that depend on the reef for survival.

Dustan said something else, too: If you really want to help, bring some weaponry to help fight back against the dreaded COT.

The explosion of COTs was first noted by Australian environmental activist Norm van’t Hoff. The boom is a consequence of runoff from human waste that’s deposited in shallow septic pits and untreated sewage discharged from boats. This nitrogen-rich stew causes a spike in phytoplankton, which COT larvae eat. More COTs survive to adulthood, when they turn to coral for their meal.

Hardcore divers come from around the world to delight in Raja Ampat’s amazing coral. Tourism has enabled locals to switch from destructive practices such as shark-finning (for shark-fin soup) and fish-bombing, where explosives are dropped over the sides of boats. The COTs threaten that tourism.

Dustan came up with a simple countermeasure: Injecting an adult crown-of-thorns starfish with a 10 percent vinegar solution kills it. Imagine something like a needle-tipped caulking gun connected to a bladder full of vinegar solution. When the COT is dead, the fish eat it.

The starfish aren’t that deep — from five to 15 feet below the surface — but to reach them easily requires a mask, snorkel and fins. These are things the residents of Raja Ampat don’t have.

So Butterworth set about collecting them so locals could fight the scourge themselves.

“We said we’d be happy to take up a drive,” said Jonas Furberg, owner of Blue Planet. “Most divers are aware enough to want to lend a hand.”

The Washington area is blessed with divers who upgrade their gear regularly. Blue Planet became a place to drop off fins and masks that were gathering dust. Before long, the shop had 45 sets of masks, fins and snorkels, including 27 snorkels Furberg donated to the effort.

In March, Butterworth flew to Indonesia with his frequent dive partner, Jan Fine, to deliver five bags’ worth of gear collected with the help of Blue Planet and its customers. Contributions also came from the Kings Cormorants Masters Swimming Club in London, Florida’s Force-E Scuba Centers and the Daventry Community Association (where Bruce lives with his wife, Kris). Cathay Pacific and Garuda Indonesia airlines waived the baggage fees.

“The big [nongovernmental organizations] and government programs are not going to fix this issue,” Dustan emailed from Raja Ampat. “They move too slow and, like politics, ecology is a local sport. People from developed nations pitching in to help locals here is a pretty high form of participation.”

Dustan said it’s important that the residents of Raja Ampat know that people from around the world care about their reefs.

Furberg is leading Blue Planet trips to Raja Ampat in November and again in December.

“For divers, coral reefs are magical,” he said. “I tell divers you will see colors down there you’ll never see on the surface.”

He also tells them: “It’s up to you to be an ocean advocate, to become tomorrow’s stewards of the ocean.”

(If you have diving equipment to give, email Bruce at . To make a monetary donation, visit the Trees to Seas Foundation at )

Twitter: @johnkelly

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