Nets, ropes, plastic waste and more from the Great Pacific Garbage Patch in 2018/Handout/The Ocean Cleanup/EPA-EFE/Shutterstock
2023.04.18 Tue posted at 16:15 JST
（ＣＮＮ） Scientists have discovered that small crabs, sea anemones and other coastal creatures form thriving communities in the ocean thousands of kilometers from their natural habitat. A large amount of plastic garbage with these organisms attached is called the “Pacific garbage patch”, and it is an accumulation of about 1.6 million square kilometers of garbage floating between California and Hawaii.
In a paper published Wednesday in the scientific journal Nature Ecology and Evolution, a team of researchers found that dozens of coastal invertebrates were less likely to be plastic debris that had floated in the oceans over the years. It was revealed that they were able to survive and reproduce on
Scientists say the results suggest that marine plastic pollution could create new drifting ecosystems. The species that make up this ecosystem are organisms that normally wouldn’t live in the open ocean.
Organic matter decomposes and sinks in a few months, or even a few years at the most, whereas plastic garbage can stay afloat for a much longer period of time. Attached organisms thus have the opportunity to survive and reproduce in the open ocean for several years.
Lynsey Hallam, a research scientist at the National Institute of Food and Agriculture and the lead author of the paper, told CNN that she was surprised by the rate at which such creatures were found. He said he confirmed its presence in 70% of the plastic waste he studied.
Plastic litter with both pelagic barnacles and bryozoans and coastal anemones
Between November 2018 and January 2019, Hallam and his team investigated 105 pieces of plastic waste that had been pulled from the Great Pacific Garbage Patch. As a result, 484 marine invertebrates consisting of 46 distinct species were identified. About 80% of these were species that normally live on the coast.
On the other hand, many species that inhabit the open ocean were also found in the plastic waste. Both groups were present in two-thirds of the litter, Hallam said.
The impact of new species populating the open ocean is not yet fully understood, he said. There’s a good chance they’re fighting over places and food, and they could be preying on each other, but it’s hard to know exactly what’s going on.
Hallam added, however, that there is evidence that some anemones feed on pelagic species, and that some sort of predatory relationship exists between the two communities.
How the native coastal creatures reach the open ocean and survive there remains a mystery. For example, there is no answer to the question of whether it was just attached to a piece of plastic litter near the coast, or whether it was able to colonize new plastic litter once it was out in the ocean.
