SIX TIMES more plastic than plankton floats in the North Pacific, and the plastic bits may be causing harm to sea life, says a new study of the largest amount of plastic ever observed in this remote stretch of ocean.
The plastic, dumped or lost by vessels or washed out to sea as urban runoff, can be swallowed by fish, sea birds such as albatross, and near-surface jellyfish-like creatures called salps, researchers involved in the study said.
"Their gut becomes filled with things they can't digest," said Steven Weisberg of the Southern California Coastal Water Research Project in Westminster, California, one of the authors of the study. The animals would "feel full, but they wouldn't be getting nutritional value."
Plankton is the collective term used for tiny plants and animals that live near the ocean surface, serving as food for a variety of creatures including whales. The plastic bits include remnants of bags, transport containers, lighters, shoes and other items.
The study to be published in the science journal, Marine Pollution Bulletin, was carried out by the Algalita Marine Research Foundation in Long Beach, with the help of Weisberg and Shelly L. Moore of the Southern California Coastal Water Research Project. Eleven ocean water samples containing thousands of bits of plastic were collected in three days of sampling in August 1999 in an area of the North Pacific between Hawaii and California. Currents move around this area, known as a "gyre", in a circular pattern, trapping and concentrating floating debris. A roughly 500 square mile zone within the gyre is known to present-day researchers as the "great garbage patch" because of its tendency to accumulate floating trash, said Curtis Ebbesmeyer, an oceanographer and expert on seaborne trash who is familiar with the new study.
The plastic can break up into tiny pieces but resists breaking down further. "The stuff doesn't go away," said Charles Moore, captain of the research vessel Alguita and an author of the study.
Other studies have found plastic among skeletons of albatross chicks, apparently fed to them by parent birds. Previous studies also have measured large amounts of plastic in the North Pacific, though this study picked up far more.
Sea turtles sometimes swallow plastic bags, likely believing they are jellyfish. Not only animals that eat plankton, but the planktonic creatures themselves can ingest minuscule plastic pieces. Since they are in turn eaten by larger animals, the plastic may well be working its way up the food chain - possibly all the way to humans, Ebbesmeyer said.
Areas like the North Pacific, where currents move in a circular pattern and concentrate floating debris, can be found in other places around the globe, but the trash study does not mean all oceans have such high concentrations of plastic, Weisberg said.
Moreover, "there is now stronger evidence for human influence on global climate," the scientists concluded in their preliminary report, which was distributed to more than 100 governments this week for review.
Several scientists familiar with the new report, prepared by an international group known as the Intergovernmental Panel on Climate Change, said its findings significantly strengthen the case for a human role in climate change. Although there is general agreement that THE CLIMATE IS WARMING, the question of how much of the change is caused by human action has been a major topic of scientific inquiry. To read the complete Los Angeles Times article visit their website at-- http://www.latimes.com/news/
science/science/20001026/
t000102313.html or click on global warming.
For more information on ocean trash, see researcher Curtis Ebbesmeyer's Web site, www.beachcombers.org.
