Human waste threatens marine life, says study

A tawny stuffed puppy bobs in cold sea water, his four stiff legs tangled in the net of some nameless fisherman.

It's one of the bigger pieces of trash in a giant patch of garbage-littered water - one that's bigger than Texas - where most of the plastic looks like snowy confetti against the deep blue of the north Pacific Ocean.

But most of the trash in the Great Pacific Garbage Patch has broken into bite-sized plastic bits, and scientists want to know whether it's sickening or killing the small fish, plankton and birds that ingest it.

During their August fact-finding expedition, a group of University of California scientists found much more debris than they expected. The team announced their observations at a San Diego press conference last week.

"It's pretty shocking - it's unusual to find exactly what you're looking for," said Miriam Goldstein, who led fellow researchers from the Scripps Institution of Oceanography at UC San Diego on the three-week voyage.

While scientists have documented trash's harmful effects for coastal marine life, there's little research on garbage patches, which were first explored extensively by self-trained ocean researcher Charles Moore just a decade ago. There's also scant research on the marine life at the bottom of the food chain that inhabit the patch.

But even the weather-beaten, sun bleached plastic flakes that are smaller than a thumbnail can be alarming. "They're the right size to be interacting with the food chain out there," Goldstein said.

The team also netted occasional water bottles with barnacles clinging to the side. Plastic sea trash does not biodegrade and floats at the surface.

The sheer quantity of plastic that accumulates in the North Pacific Gyre, a vortex formed by ocean and wind currents and located 1600km off the California coast, has the scientists worried about how it might harm the sea creatures there.

The Scripps team hopes the samples they gathered during the trip nail down answers to questions of the trash's environmental impact. Does eating plastic poison plankton?

Is the ecosystem in trouble when new sea creatures hitchhike on the side of a water bottle?

Plastics have entangled birds and turned up in the bellies of fish, and one paper cited by the National Oceanic and Atmospheric Administration estimates 100,000 marine mammals die trash-related deaths each year.

The scientists hope their data gives clues as to the density and extent of marine debris, especially since the Great Pacific Garbage Patch may have company in the Southern Hemisphere, where scientists say the gyre is four times bigger.

- NZPA