Marine Biodiversity is the theme for this year's International Day for Biological Diversity (IDB). 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.