The oceans’ plastic killing fields

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Continents of garbage in the oceans are killing marine life and releasing poisons that enter the human food chain, Amanda Woods writes in the Sydney Morning Herald

In one of the few places on Earth where people can rarely be found, the human race has well and truly made its mark. In the middle of the Pacific Ocean lies a floating garbage patch twice the size of Britain. A place where the water is filled with six times as much plastic as plankton. This plastic-plankton soup is entering the food chain and heading for your dinner table.

For hundreds of years, sailors and fisherman have known to avoid the area between the Equator and 50 degrees north latitude about halfway between California and Hawaii. As one of the ocean’s deserts, the North Pacific Subtropical Gyre lacks the wind that sailors need to survive, as well as the nutrients to support large fish or the men who hunt them.

But 10 years ago, Captain Charles Moore took a short cut through the airless doldrums in his catamaran, Alguita, and caught sight of something that changed his life. As he looked out at what should have been a clear blue ocean, Moore saw a sea of plastic. As far as he could see, day after day, were bottles, wrappers and fragments of plastic in every colour.

Historically, the ocean’s circular currents have led to accumulation of flotsam and jetsam in the subtropical high, where the waste has biodegraded with the help of marine micro-organisms. But since humans developed a material designed for durability, which can survive exposure to any bacteria, the gyre has been filling with a substance it can’t get rid of. Rather than biodegrading, plastic photodegrades, breaking down in the sunlight into smaller and smaller pieces. But no matter how small it gets, it’s still plastic, and causes havoc when it enters the stomachs of marine life.

Ian Kiernan, the Australian who founded Clean Up the World, started his environmental campaign 20 years ago after he became appalled by the amount of rubbish he saw on an around-the-world solo yacht race. He’ll never forget the first time he saw the gyre.

“It was just filled with things like furniture, fridges, plastic containers, cigarette lighters, plastic bottles, light globes, televisions and fishing nets,” Kiernan says.

“It’s all so durable it floats. It’s just a major problem.”

He picks up an ashtray filled with worn-down coloured pieces of plastic. “This is the contents of a fleshy-footed shearwater’s stomach,” he says. “They go to the ocean to fish but there ain’t no fish – there’s plastic. They then regurgitate it down the necks of their fledglings and it kills them. After the birds decompose, the plastic gets washed back into the ocean where it can kill again. It’s a form of ghost fishing, where it goes on and on.”

With gyres in each of the oceans, connected by debris highways, the problem isn’t restricted to the North Pacific Gyre. It is estimated there are more than 13,000 pieces of plastic litter on every square kilometre of the ocean surface.

The United Nations Environment Program says plastic is accountable for the deaths of more than a million seabirds and more than 100,000 marine mammals such as whales, dolphins and seals every year. A Dutch study in the North Sea of fulmar seabirds concluded 95 per cent of the birds had plastic in their stomachs. More than 1600 pieces were found in the stomach of one bird in Belgium.

Source : Sydney Moening Herald. The full article can be found at http://www.smh.com.au/news/environment/the-plastic-killing-fields/2007/12/28/1198778702627.html?page=fullpage#contentSwap1