Ocean species found living on the ‘Great Pacific Garbage Patch’
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Covering 620,000 square miles or three times the size of France, the Great Pacific Garbage Patch is the largest accumulation of ocean plastic in the world.
Located halfway between Hawaii and California, it is a jumble of plastic bottles, microplastics, fishing gear and more, all carried along by the ocean currents.
Now scientists have discovered that the patch is home to marine invertebrates that live and reproduce there, including clams, oysters and crustaceans.
Most of those found on the huge patch by the US researchers mostly live only in coastal regions of the Western Pacific.
Researchers have already shown that harmful microbes can hitch a ride on microplastics and spread across the ocean.
Garbage patches are large areas of the ocean where litter, fishing gear and other debris – known as marine litter – collects. The most famous of these patches, the Great Pacific Garbage Patch, is located in the North Pacific Gyre (between Hawaii and California). Pictured are cleanup efforts on part of the patch by The Ocean Cleanup
The GPGP covers an estimated area of 620,000 square miles, an area twice the size of Texas or three times the size of France
The study was led by Linsey Haram of the Smithsonian Environmental Research Center in Maryland and is published today in Natural Ecology & Evolution.
The authors suggest that this discovery indicates that species that originated on the coast are able to survive and reproduce on plastic debris that has traveled thousands of miles over several years.
They may represent a new type of ecological community in the ocean — which they call a “neopelagic community” — that can compete for space and other resources on plastic “rafts.”
“We show that the high seas are colonized by a diverse array of coastal species, which survive and reproduce in the open ocean, greatly contributing to floating community composition,” say Haram and colleagues.
It appears that coastal species now persist in the open ocean as a substantial part of a neopelagic community supported by the vast and expanding sea of plastic debris.
“The plastisphere may now provide extraordinary new opportunities for coastal species to expand populations into the open ocean and become a permanent part of the pelagic community.”
Plastic is known to fall into our rivers or be washed up by tides onto beaches, carried by currents before ending up in the open ocean.
These plastics are broken down by waves and sunlight into tiny microplastics, which can be mistaken for food by marine life with fatal consequences.
The Ocean Voyages Institute’s marine plastic recovery vessel, S/V KWAI, after a 48-day expedition, successfully removing 103 tonnes (206,000 lbs.) of fishing nets and consumer plastic from the Great Pacific Garbage Patch in 2020
The animation and images on this page show the location and concentration of floating plastic between April 2017 and September 2018. Data was collected between approximately 38 degrees north latitude and 38 degrees south latitude, the observation range for the CYGNSS mission
Ultimately, plastic becomes trapped in the centers of ocean basins or subtropical “gyres”—large systems of rotating currents in each of the five major oceans.
Unfortunatelythe world’s five subtropical eddies may harbor “garbage patches” made up of plastic waste, fishing gear and other debris.
The Great Pacific Garbage Patch, between California and Hawaii, is most famous for having a lot of shipping traffic passing through it.
According to NASA, about 8 million tons of plastic flows from rivers and beaches into the ocean every year.
For the new study, the team collected 105 pieces of floating plastic debris from the patch between November 2018 and January 2019.
Many items showed advanced deterioration from having been at sea for ‘many years’, such as household items.
‘Many plastic containers and baskets, usually at least 3-5 mm thick, were now wafer-thin and very friable,’ say the researchers.
Overall, they found evidence of living coastal species on 70.5 percent of the debris analyzed.
They identified 484 marine invertebrates on the debris, 80 percent of which were species normally found in coastal habitats.
Examples were crustaceans of the amphipod order (Elasmopus rapax and Calliopius pacificus), mussels (Musculus cupreus), sea anemone (Diadumene lineata) and the Pacific oyster (Crassostrea gigas).
The number of coastal species such as arthropods and molluscs identified during plastic rafting was more than three times greater than that of pelagic species normally living in the open ocean.
They note that diversity of all organisms was highest on ropes and fishing nets harbored the greatest diversity of coastal species.
Creatures found in the dump included crustaceans, clams, sea anemones and the Pacific oyster (Crassostrea gigas, pictured)
The authors also identify evidence of sexual reproduction in both coastal and open-ocean species, including in hydroids (relatives of jellyfish and corals) and amphipods and isopods (both types of crustaceans).
“The presence of reproductive females and different size classes for coastal crustaceans and cnidarians suggests that coastal species are reproducing and possibly self-recruiting and continually populating their parent rafts,” they say.
More research is now needed to understand how the species survives and what the “ecological and evolutionary consequences” are, they conclude.
“With the production of waste from plastic pollution and inputs into the ocean expected to increase exponentially over the coming decades, a steady source of substrate could sustain the neopelagic as a tenacious community,” they say.
“Future research should also investigate to what extent the patterns observed in the North Pacific occur in other ocean eddy systems.”