Ahoy there, buccaneers. ‘Tis I, returned from the briny depths for another fishy update. And this one’s a sad tale, me hearties, for anyone who’s ever appreciated the beauty of a coral reef. Even ye landlubbers out there may know what I mean, what with all your fancy “snorkel gear” — me, I wouldn’t be caught dead in a get-up involving the word snork, but you lot seem to enjoy it. And I enjoy the pointin’ and laughin’ from atop me crow’s nest. Arrrr!

But I digress. Today, I share news of what some researchers are calling an “underwater Holocaust.” They say record hot water temperatures followed by disease have caused the biggest loss of Caribbean reefs in history.

“It’s an unprecedented die-off,” said National Park Service fisheries biologist Jeff Miller, who last week checked 40 stations in the Virgin Islands. “The mortality that we’re seeing now is of the extremely slow-growing reef-building corals. These are corals that are the foundation of the reef … We’re talking colonies that were here when Columbus came by have died in the past three to four months.”

Calling the corals “the goose with the golden eggs,” one researcher notes that these reefs are essential to the survival of small-island economies, providing many billions of dollars in tourism and commercial fishing monies. They’re home to many key fish species, limit the damage from hurricanes and tsunamis, and could even be sources for undiscovered medicines. For the first time, scientists are seeing entire colonies die off, including an 800-year-old, 13-foot-high star coral colony found dead in the waters off Puerto Rico recently.

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Many scientists, like the aptly named prof M. James Crabbe, believe global warming is to blame for the warmer water temps. Crabbe asserts that the corals won’t be able to adapt quickly enough to the changing climate. The warmer waters can cause the corals to “bleach,” or reject the algae giving the coral its color — and its nutrients. If temperatures return to normal, bleached coral can recover, once again accepting the algae. But last year, the Caribbean corals were struck by disease — some caused by human sewage in the waters — and have died off as a result.

Unfortunately, coral reefs — and ocean issues in general — fall victim to the “out-of-sight-out-of-mind” way of thinking. “If 40 percent of the trees in one of our national parks died,” says biologist Caroline Rogers, “people would take notice.”

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Arrrgh. ‘Tis true, mateys, and that’s the major reason for this column. I’ve me spyglass trained on the most pressing ocean issues of the day. And I aim to weigh anchor and spout about them any chance I get. ‘Ave you any fishy stories to tell? Leave ’em in comments.