The Great Pacific Garbage Patch, also known as the Pacific trash vortex, spans from the waters off the east coast of Japan to the waters off the west coast of California. It is bound by the North Pacific Gyre, a circular system of ocean currents that concentrates plastic pollution into two specific zones: the western garbage patch near Japan and the eastern garbage patch near California. The North Pacific Subtropical Convergence Zone links these two patches together. This convergence zone forms where cool Arctic water meets warm South Pacific water and acts as a passageway that can move debris from one patch to another.
The existence of the Pacific Ocean garbage patch was predicted by a 1989 scientific paper published by the National Oceanic and Atmospheric Administration. Several Alaska-based scientists studied the characteristics and distribution of surface plastic in the Pacific for a period of four years. The scientists proposed that a combination of surface currents, winds, and microscale convergences locally concentrated the plastic in the North Pacific and increased its probability of entering into food chains.
The remains of an albatross at Midway Atoll containing ingested plastic pollution
The garbage patch was first visibly identified by oceanographer Charles J. Moore in the late 1990s. He discovered a vast area of the ocean where in certain spots plastic pollution outweighed living biomass six to one. “There were shampoo caps and soap bottles and plastic bags and fishing floats as far as I could see,” Moore said, “Here I was in the middle of the ocean, and there was nowhere I could go to avoid the plastic” (see Charles Moore speak about the Pacific garbage patch here). Since its discovery, there has been significant research conducted on the Great Pacific Garbage Patch, and new hazards are being detected as the patch continues to increase in size and intensity.
New Dangers
Recently, a tiny organism has been found to be wreaking havoc on coral reefs located near the Great Pacific Garbage Patch. Halofolliculina is a small, single-celled ciliate that is thriving in the plastic-filled waters of the North Pacific. Halofolliculina is a pathogen that causes skeletal eroding band disease in corals, and it is thriving in the so-called “plastisphere” of the North Pacific Gyre.
Halofolliculina (Photo by Hank Carson)
Contrary to what you may expect, excessive trash in the ocean is not universally harmful to all organisms. Plastic pollution in the Great Pacific Garbage Patch is hazardous to birds and certain fishes that mistakenly ingest it; but other organisms, such as Halofolliculina, are finding the assorted plastic pieces to be ideal surfaces to live on.
While this is great for Halofolliculina, it can be devastating for corals. Skeletal eroding band disease was first observed on coral reefs around the Hawaiian Islands in 2010. While it is not certain how the disease reached the islands, it is likely that the massive amounts of plastic pollution that wash up on the Hawaiian Islands every day harbor some Halofolliculina. This could transport skeletal eroding band disease to Hawaiian corals when they otherwise would not have been exposed to it.
