I know what you’re thinking, that something other than the burdensome responsibilities of investigative journalism is involved in my decision to go back to Key West this Memorial Day weekend.

But my concern about the plight of endangered species there goes beyond those crawling from pub to pub along Duval Street, chilling with all six toes around the Hemingway House or eating fire as the sun sets nightly on Mallory Square.

There is, actually, a dead serious threat to marine life not only in the Gulf of Mexico, but in all the world’s oceans from the unbelievably-damaging British Petroleum “Deepwater Horizon” oil spill that has been gushing undeterred for over a month. That threat is to the global role the living coral reef seven miles from Key West plays.

As National Geographic contributor and oceanographer Sylvia Earle testified to Congress last week, “The Gulf of Mexico is not, as some believe, an industrial wasteland, valuable primarily as a source of petrochemicals and a few species of ocean wildlife that humans exploit for food, commodities and recreational fishing…The Gulf of Mexico is a living laboratory, America’s Mediterranean, a tri-national treasure…(playing) a vital role in generating oxygen, taking and holding carbon, distributing nutrients, stabilizing temperature, yielding fresh water to the skies that returns them as rain – contributing to the ocean’s planetary role as Earth’s life support system.

“Life in the sea, after all, supports the basic processes that we all take for granted – the water cycle, the oxygen cycle, the carbon cycle, and much more. With every break we take, every drop of water we drink, we are dependent on the existence of Earth’s living ocean.”

We know more about the Moon than we do about what’s beneath the Gulf of Mexico, three miles deep in some places, she noted. In the first of an eight-volume series on The Gulf of Mexico Origin, Waters, and Biota, there are 79 chapters contributed by 140 authors from 80 institutions in 15 countries that identify 15,419 different species in the Gulf “embracing most of the large categories of life on Earth,” she said.

Seven miles off shore from Key West is a massive living coral reef. “Living” means it’s occupied by tiny sea animals that create and live inside the rock coral. One can observe Key West’s reef extensively from glass-bottom boats that depart daily from Mallory Square.

The reef teems with tropical fish, hard and soft corals, sponges, snails, jellyfish, anomes, crabs, lobsters, rays, sea turtles, nurse sharks and in total more than 110 species of coral and 500 species of tropical fish.

Key West’s living reef is one of only three living reefs in the world’s oceans, the second largest after the Great Barrier Reef off the northeastern coast of Australia. These living reefs function as a primary filtration system for all the oceans on the planet, and without them, the oceans could not support any life at all.

Kill off Key West’s living coral reef, in other words, and marine life not only in the Gulf of Mexico but in the world’s oceans as a whole, is seriously jeopardized.

Key to the living reef are the living animal polyps, themselves, who live in the calcified housing they create. For the coral reefs to be effective as filtration systems, they need to be occupied by those living creatures.

But that’s not the whole story. The reason the reef remains living has everything to do with a small, unassuming species of fish known as “parrot fish.”

These colorful little fish are, in fact, the workers that constantly repair the reef, and therefore are indispensable for sustaining it. They eat the coral rock, digest it and then excrete it as a fine sand that fills in like putty the cracks and tears in the reef.

This remarkable symbiotic relationship between the reef and the parrot fish is a mind-boggling wonder of creation. The fish also eat algae that can choke coral and otherwise tend to a reef’s health and survival.

Above all else, extraordinary means must be found to protect this living coral reef from the oil spill, and from the even more toxic chemicals being used in the attempt to disperse it.