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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 Deep

In the absence of sunlight, many deep sea fish create lights of their own, in the form of bioluminescent symbiotic bacteria that dangle as lures or shine a path ahead like headlights. Marine invertebrates burrow through the silt of the seabed itself.

Seamounts, underwater mountains that climb 1,000 meters or more from the ocean floor, often have complex surfaces of terraces, pinnacles, ridges, crevices and craters, and their presence diverts and alters the currents that swirl about them; the net effect is to create a variety of living conditions, providing habitat for rich and diverse communities. There are believed to be in excess of 100,000 seamounts of 1,000 meters or higher, although only a fraction has been studied.

Perhaps most unique and remarkable of all are the ecosystems that surround hydrothermal vents and cold-water seeps. Hydrothermal vents occur in volcanically active areas of the seafloor, where super-heated gases and chemically-rich water erupt from the ground at temperatures of up to 400 degrees C. Microbial organisms are able to withstand these extreme temperatures to create energy from the chemical compounds being forced up through the floor. Some of these microbes live symbiotically inside tubeworms, while others form large mats, which attract progressively larger organisms that graze on them. So far, over 500 species have been discovered that live only at hydrothermal vents; it is possible that these communities are the oldest ecosystems on Earth, and that vents are where life began.

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  • United Nations
  • United Nations Environment Programme