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IDB2012 booklet

IDB 2012

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The Green Wave

International Day for Biological Diversity 2012


Marine Biodiversity was the theme for International Day for Biological Diversity (IDB) in 2012. Designation of IDB 2012 on the theme of marine ecosystems provides Parties to the Convention on Biological Diversity (CBD) and everyone interested in marine life, the opportunity to raise awareness of the issue and increase practical action.


How Much Life Is in the Sea?

From 2000 to 2010, an unprecedented worldwide collaboration by scientists around the world set out to try and determine how much life is in the sea.

Dubbed the ‘Census of Marine Life’, the effort involved 2,700 scientists from over 80 nations, who participated in 540 expeditions around the world. They studied surface seawater and probed the deepest, darkest depths of the ocean, sailed tropical seas and explored ice-strewn oceans in the Arctic and Antarctic.

By the time the Census ended, it had added 1,200 species to the known roster of life in the sea; scientists are still working their way through another 5,000 specimens to determine whether they are also newly-discovered species. The estimate of the number of known marine species - the species that have been identified and the ones that have been documented but await classification - has increased as a direct result of the Census efforts, and is now around 250,000. (This total does not include some microbial life forms such as marine viruses.) In its final report, the Census team suggested it could be at least a million. Some think the figure could be twice as high.


Marine and Coastal Biodiversity

Along the Coast

The Continental Shelf

The Open Ocean

The Deep

Great Migrations

The Human Impact

Causes of Decline

A Warmer Ocean

A More Acidic Ocean

The Problem of Over-Fishing

Why We Should Care

Blue Carbon

The Value of Marine Reserves

CBD and the Jakarta Mandate


The Open Ocean

Peering over the sides of a ship steaming over its surface, it might appear that the open ocean is one big, boundary-free expanse of water, its wildlife swimming back and forth, from surface to depths, without constraint. But Census of Marine Life researchers found that, although many areas of the open ocean may look equal, to marine animals there are clear differences.

The researchers found, for example, that white sharks congregate in an area off Hawaii that scientists dubbed the “white shark café”, and that several species of turtles, seabirds, seals, whales and sharks all congregate at ‘hotspots’ such as in the California Current.

The top 100 meters of the ocean is the zone within which most of the life with which we are instantly familiar – most of the fish, turtles, and marine mammals, as well as the microscopic plant and animal plankton that forms such an important part of the marine food web – primarily resides. Much deeper than that, and sunlight struggles to penetrate. Six hundred meters deep, sunlight in the ocean is as bright as starlight on the surface; at 693 meters it is approximately ten-billionth its surface brightness; and by 1,000 meters, the sea is completely dark.

And yet, even here, there is life.

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  • United Nations
  • United Nations Environment Programme