In the North Pacific lies a giant trash patch made of plastic waste. The floating island weighs around 80,000 tonnes and covers an estimated area of 1.6 million square kilometers – that’s twice the size of Texas and three times the size of France.
Plastic islands form when surface currents push litter from the coast to regions with rotating currents, where it is trapped. The pile grows larger over time as more and more trash accumulates.
The world has at least five such mounds, with the “Great Pacific Garbage Patch” in the North Pacific between California and Hawaii being the largest.
Experts monitor these environmental disasters, trying to find ways to solve the problem.
Now in a new commentary piece published in the journal Nature Communication, scientists have discovered that marine species have begun to colonize the plastic.
That’s not a good thing, say the paper’s authors.
“Plastic problems go beyond simple ingestion and entanglement,” Linsey Haram, lead author of the paper and former postdoctoral fellow at the Smithsonian Environmental Research Center (SERC), said in a press release.
“This creates opportunities for the biogeography of coastal species to expand significantly beyond what we previously thought possible.”
Scientists first suspected that creatures could use the plastic to survive on the high seas in 2011, following the Japanese tsunami. In the years that followed, nearly 300 species were found clinging to various pieces of tsunami debris floating across the Pacific, some finding their way to North America, invasive species in tow.
But sightings of animals on plastic in the open ocean have been rare, according to the study authors.
For their article, Haram worked with a non-profit organization called Ocean Travel Institute, which collects plastic pollution, and a duo of oceanographers from the University of Hawaii named Jan Hafner and Nikolai Maximenko.
Using prediction models created by Hafner and Maximenko to determine where plastic was most likely to accumulate in the Great Pacific Garbage Patch, the Ocean Voyages Institute set out to collect trash – over 103 tons over the course of the first year of the pandemic alone, the authors say.
Some of these samples were shared with Haram. The analysis revealed the colonization of several coastal species, including “anemones, hydroids and shrimp-like amphipods” which appear to be “thriving” on the trash island.
“Until now, the open ocean has not been habitable for coastal organisms,” said SERC senior scientist Greg Ruiz. noted.
“Partly because of habitat limitation – there was no plastic there in the past – and partly, we thought, because it was a food desert.”
Obviously – this is not true. Scientists are now observing plants and animals in a new habitat, and they are somehow managing to sustain themselves. A problem arises when considering native species that colonize floating debris in the open ocean. Competition with new coastal species could disrupt the ecosystem, Haram says.
Plastic, which comes from different points around the world, also increases the risk of carrying invasive species, much like the situation that occurred with tsunami debris.
The next step, scientists say, is to dive deeper into these deep-sea colonies and find out what drives them and the risks they may pose to local ecosystems.
“Coastal species are in direct competition with these ocean rafters,” Haram said.
“They’re competing for space. They’re competing for resources. And those interactions are very poorly understood.”
Thumbnail image created by Cheryl Santa Maria. Plastic bag: Sarah2/CanvaPro