mohandasgandhi: Scientists call for protected...

High-res

Scientists call for protected areas to conserve deep sea environment: Waste dumping, fishing, mining and climate change are transforming the deep sea ecosystem faster than scientists can study it

There’s trouble in the depths. The deep sea is the last true wilderness on Earth, but 1,800 km below the surface, an environmental crisis is growing.

On Monday scientists at the Census of Marine Life (COML) project, the 10-year assessment of the world’s oceans completed in 2010, published their analysis of the impact humans are having on the deep sea. Their conclusions were stark: the largest habitat on Earth is being damaged by pollution, resource exploitation and climate change.

The deep sea accounts for 73% of the oceans, an area of 360 million square kilometres. It is a world completely unlike our own. Sunlight cannot reach the depths and the only flickers of light come from living things that use bioluminescence for hunting or disguise.

Far from being a barren wasteland, the deep sea is teeming with life. From vampire squid to blobfish, these extraordinary animals are found nowhere else and their habitats are as unusual as the creatures themselves. Hydrothermal vents, for example, spew out a variety of chemicals on which communities of bacteria can survive without any need for sunlight. There are even forests of coral adapted to live in the cold and dark, providing shelter for more than a thousand animal species.

All of this is under threat. Writing in the journal PLoS One, scientists led by Eva Ramirez-Llodra of the Institute of Marine Science in Barcelona conclude that humans are having severe impacts on the deep sea. In the past it was the dumping of waste that caused the most harm. “Approximately 6.4 million tonnes of litter per year is dropped into the oceans,” they write.

Plastics are of particular concern. “There is accumulating evidence that ‘mermaids’ tears’ (5mm in diameter) and microplastics (microscopic sand grain-sized particles of eroded plastic) are becoming more common in the world oceans,” says the report. “Little is known however, of the true effect of these particles on the environment and fauna.”

The main problems today are fishing and mining. Deep-sea trawling, say the researchers, is particularly damaging because the species caught are “often long lived, with slow growth and delayed maturity making them poorly adapted to sustain heavy fishing pressure.”

(Read more)

[Image via NOAA]