The 14 million tons of plastic entering the world’s oceans each year are a known threat to wildlife, and the latest research shows marine trash could have new consequences for marine animals. Scientists have discovered that coastal critters and plants like crabs, anemones and seaweed have found a way to survive in the open ocean by colonizing rafts of floating plastic debris. An accumulation of trash known as the Great Pacific Garbage Patch is acting as a new type of ecosystem, ferrying species hundreds of miles from their usual coastal habitat into the high seas.
In the work published this month in Nature Communications, researchers found that marine species like barnacles, brittle stars and shrimp-like crustaceans called isopods living among the garbage patch that floats roughly halfway between the coast of California and Hawaii. The species appear to be thriving on rubbish rafts despite harsh conditions of the open ocean, where there’s often little food and shelter.
“It’s creating opportunities for coastal species’ biogeography to greatly expand beyond what we previously thought was possible,” said Linsey Haram, a research associate at the Smithsonian Environmental Research Center and coauthor of the study, in a statement.
The Great Pacific Garbage Patch is difficult to spot with the naked eye—much of the “patch” is a collection of tiny fragments of plastic gathered by ocean currents called gyres. Other parts of the trash raft have items that are easier to see, like buoys, nets, and even fishing vessels. The Great Pacific Garbage Patch, which is roughly twice the size of Texas, is estimated to be the biggest marine trash accumulation with an estimated 79,000 metric tons of debris and is growing rapidly.
"All sorts of stuff ends up out there," says Haram to the BBC’s Victoria Gill. "It's not an island of plastic, but there's definitely a large amount of plastic corralled there."
In the study, researchers examined plastic items more than two inches in diameter gathered in North Pacific Subtropical Gyre, which hosts the Great Pacific Garbage Patch. The team carefully searched for signs of life in garbage pulled from the patch, including old fishing gear and household items like toothbrushes. They found more than 40 coastal species like marine bugs, mollusks, and crustaceans on 90 percent of the marine debris they studied.
“It’s almost like a new island has emerged,” says Greg Ruiz, a scientist with the Smithsonian Environmental Research Center and coauthor of the report, to Evan Bush for NBC News.
While the species colonizing the marine trash seemed to be thriving on the floating plastic detritus, scientists are concerned that plastic rafts could help ferry species to new regions. Researchers have known that natural marine detritus like logs and seaweed can host coastal organisms, but these rafts have short life spans compared to those made of plastic, reports Popular Science’s Kate Baggaley. Another unanswered question is how these coastal hitchhikers could compete with the open ocean’s native flora and fauna, which already make their home on floating debris. The authors concluded that rafts of coastal species in the open ocean will likely become more prevalent as marine plastic pollution continues.
“There are so many questions at this point about what the ecological impacts are,” says Haram to Popular Science. “We can expect to see more and more plastic ending up in the middle of the ocean and if our research is any indication that may mean more coastal species as well.”