First Marine Census Describes the Wonders–and Troubles–of the Seas

By Eliza Strickland | October 4, 2010 8:58 am
Cirrate octopod, found at around 800m in the Gulf of Maine
View inside mantle
Poster.  Hidden Ocean Expedition

Marine scientists have completed the first ever census of the myriad creatures living in the world’s deep blue seas, a monumental accomplishment that took 2,700 researchers 10 years to accomplish. While the scientists didn’t count every single fish head, they now know more than ever before about what kinds of life inhabit the oceans, what lives where, and the number of creatures that remain. They hope that this sound science will produce sound decisions on environmental policy and fishery management.

The Census of Marine Life was officially launched in 2000. After a decade of work, some of the most interesting findings are the delineations of the ocean’s unknowns. For example, the Census upped the estimate of the number of known marine species to nearly 250,000, but still couldn’t estimate the total number of species in the ocean. It might be millions, the report says, or tens or hundreds of millions, when all the ocean’s microbes are accounted for.

The information gathered by the census has been organized into a global marine life database, but it’s far from a complete reckoning of the ocean’s denizens. A summary report of the Census’s findings says that “for more than 20 percent of the ocean’s volume, the Census database still has no records at all, and for vast areas very few.” Still, researchers say this information will provide a rough baseline, a reference point against which to measure the changes to the ocean’s populations. That will help researchers measure the impact of the warming water temperatures brought on by climate change, and can help them assess the impact of oil spills.

Some of the news from the census was ominous. A study of 10 groups of large, commercially important marine animals (such as reef fish, whales, sharks, and open ocean fish like tuna) found that at their lowest point, these groups had declined by nearly 90 percent from their historic baselines. However, after reaching their low points a few of these groups have shown signs of recovery–a hopeful indication that conservation programs can work. On the other end of the food chain, researchers found evidence of a global but patchy decline in phytoplankton, the tiny photosynthetic organisms that are a crucial source of food for many ocean critters.

Despite such worrisome news, the Census is also a celebration of the ocean’s diverse wonders. As the summary report says:

The Census found living creatures everywhere it looked, even where heat would melt lead, seawater froze to ice, and light and oxygen were lacking. It expanded known habitats and ranges in which life is known to exist. It found that in marine habitats, extreme is normal. [Highlights of a Decade of Discovery (pdf)]

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CATEGORIZED UNDER: Living World, Photo Gallery, Top Posts
  • Rhacodactylus

    Just wanted to say that the pics are AMAZING! Thanks


  • Michael Jennings

    The photos should have captions identifying the animals.

    Also, I doubt this statement: “The Census found living creatures everywhere it looked, even where heat would melt lead…”

    Lead melts at 327.46 °C or 621.43 °F. My understanding is that the organic substances of life cannot withstand that temperature.

    About the blobfish in the photo above: Female blobfish think he’s cute.

  • richtaur

    Just beautiful! And … frightening ;|

  • Nate

    @Michael Jennings: Thermal vents can reach 400C. This is lava in contact with highly-pressurized seawater at tremendous depths.

    At the “mere” melting point of lead, some of these creatures might “freeze to death” (have too low a temperature to support the processes that keep them alive).

    “It’s life, Jim, but not as we know it.”

  • mrbfd

    Why not say how many pretty pictures there are & number them as they are being viewed?

  • damian

    Who needs to send a probe to Titan or Europa to find bizarre alien life forms? These images are astounding.

  • reņģis

    I would love to see the same pictures in a high resolution and I’m annoyed that anyone considers the currently offered resolution adequate.

  • Lincoln

    All these images are astounding. That “fathead” fish looks like a sad Ziggy.

  • Phyllis Bourne

    Hi Michelle,
    Thanks for sharing these photos. I love them!


  • Dee

    Simply AMAZING! I’ve always been fascinated with underwater sea creatures. Thanks to the people who have the courage to discover such findings.

  • Ed Gould

    Like others I wish the pictures were of higher quality.
    Does anyone have a source for high quality pictures?

  • Eliza Strickland

    I don’t know if they’re higher resolution, but you can find lots more photos at the Census for Marine Life’s image gallery.

  • Bill Guinan

    Thank you for your amazing photos and the outstanding work you are doing.


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