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International Day for Biological Diversity
22 May

"Despite its importance, marine biodiversity — the theme of this year's International Day for Biological Diversity — has not fared well at human hands. Commercial over-exploitation of the world’s fish stocks is severe. Many species have been hunted to fractions of their original populations"

UN Secretary-General Ban Ki-moon
Message for 2012

2012 Theme: Marine Biodiversity

The oceans cover 70% of the planet’s surface area, and marine and coastal environments contain diverse habitats that support an abundance of marine life. Life in our seas produces a third of the oxygen that we breathe, offers a valuable source of protein and moderates global climatic change. Some examples of marine and coastal habitats include mangrove forests; coral reefs; sea grass beds; estuaries in coastal areas; hydrothermal vents; and seamounts and soft sediments on the ocean floor a few kilometres below the surface.

Why Marine Biodiversity?

Facts & Figures

  • Fisheries provide over 15% of dietary intake of animal protein
  • 40% of world’s population lives within 100 kilometers of the coast
  • Toxins in some marine species may yield anti-cancer drugs and other pharmaceuticals worth more than US$5 trillion
  • Coastal ecosystems provide services and protection from stores that are valued at nearly US$26 billion annually
  • One third of the world’s fish stocks are over-exploited
  • 30- 35% of the global extent of critical marine environments are estimated to have been destroyed.

The survival of marine and coastal ecosystems and biodiversity is essential to the nutritional, spiritual, societal and religious well-being of many coastal communities. But even for the many millions of people who may not think that they have any strong reliance on the ocean, marine ecosystems and wildlife provide all kinds of benefits.

Without life in the ocean, there would be no life on Earth.

The ocean world is in all our daily lives:

Most importantly of all, tiny marine plants called phytoplankton produce energy, like plants on land, through photosynthesis. As a result of that photosynthesis, they release oxygen. In fact, phytoplankton release half of all oxygen in the atmosphere.

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.

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