On dry land, the U.S. Census Bureau is tidily wrapping up work on the Great 2010 Census of Humans (and coming in nicely under budget, at that). Meanwhile, out in the seven seas, a different kind of census—wetter, wider and most surely wilder—is also coming to a much-anticipated conclusion.

Ten years in the making, the spectacular Census of Marine Life is assembling the first ever catalog of all sea-faring residents, uncovering far more personal details than your census form ever dared to ask: where these species live and vacation, their numbers (historical, present and trending), the roles they play in the ecosystem, and more.

Earlier this month, COML scientists released a sneak preview of their findings, a roll call of salty friends from 25 key ocean areas, ranging from the intimidating:

Imagine living in the sea where it is permanently dark, cold, and food is hard to find. For many animals at depth it may be weeks to months between meals. If you find something to eat, you have to hang on to it. This is why so many deep-sea fishes have lots of big teeth. This dragonfish even has teeth on its tongue! They would be terrifying animals if they weren’t the size of a banana. © Dr. Julian Finn, Museum Victoria.

…to the many-legged:

Hermodice carunculata. The bearded fireworm is a type of bristleworm, with groups of white bristles along each side. The bristles are hollow, venom-filled chaeta which easily penetrate the flesh and break off if this worm is handled. They produce an intense burning irritation in the area of contact, hence the common name of the species. © Eduardo Klein.

…to the ones that rather resemble hairy eyeballs:

Atolla wyvillei. Deep-sea jellyfish. When attacked by a predator, it uses bioluminescence to "scream" for help. This amazing light show is known as a burglar alarm display. East of Izu-Oshina Island, 805m depth by ROV Hyper Dolphin. © JAMSTEC.

Far from being an exercise in scientific curiosity, COML goes a long way in filling critical gaps in our knowledge of the ecosystem that covers a whopping 70 percent of our world. Before COML got underway, we had just skimmed the surface—literally. Less than 5 percent of the oceans had been explored, with hardly any of that in the deep reaches where the majority of water (and life) lies.

Interesting tidbits from the COML preview of the 25 areas:

– Most populous species? Crustaceans (from lobsters to barnacles), at nearly 20 percent.

– Least populous? The “other vertebrates” category (includes familiar faces like whales and turtles), at a miniscule 2 percent.

– Beware: Many aliens have invaded the Mediterranean, New Zealand and Baltic waters. (Invasive species, not the intergalactic variety.)

– Rich in every way: “Even less diverse regions such as the Baltic or Northeast USA still have about 4,000 known species.”

– How much else is out there? “For every marine species of all kinds known to science, Census scientists estimate that at least four have yet to be discovered.”

COML quite clearly underscores the rich biodiversity in our oceans, and the need to build a foundation of knowledge so that we can be better informed on how to sustain populations, reverse loss of habitat and pollution damage, and more.

Ocean-focused work like Earthjustice’s case on the devastating effects of seismic surveys on sensitive wildlife like whales and dolphins, and our examination of the 1.8 million gallons of chemical dispersant used in the Gulf of Mexico (to unknown effect on marine inhabitants) spotlight the significance of this diversity and the need to protect it from the ever-growing threat of human activity.

In an interview with the Vancouver Sun, Ron O’Dor, senior scientist with COML, didn’t beat around the bush when discussing the importance of marine life:

With about half the world’s oxygen supplied by the ocean, the value of the project is vital, he said. "It’s like flying an airplane that is held together by rivets and the rivets are popping off. You are never quite sure how many can pop off before the plane falls apart and crashes to the ground."

Meanwhile, Dr. Nancy Knowlton, another project leader, tells us:

The sea today is in trouble. Its citizens have no vote in any national or international body, but they are suffering and need to be heard.

Keep a close ear out for COML’s final summary, to be released in October this year. Fortunately, you don’t have to wait to read about Earthjustice’s ocean work; there’s plenty right here at unEARTHED, and even more on our website.

More Reads:

• Census of Marine Life
• Marine Biodiversity and Biogeography – Regional Comparisons of Global Issues, PLoS ONE
• Record-Breaking Sea-Creature Surveys Released (video), National Geographic