A new study reports coastal marine species at home and thriving on the North Pacific Subtropical Gyre, estimated to be the largest ocean debris patch on the planet.
How did they get there? They “rafted” their way to the massive site aboard ocean debris, much of it plastic. In fact, scientists already knew of hundreds of coastal Japanese marine species that had “rafted” their way to Hawaii and the US west coast aboard debris from the East Japan Tsunami—products of “the largest ocean rafting event known in scientific literature to date,” according to the study’s authors.
These coastal marine residents were able to survive, grow and reproduce for years on the open ocean, surprising scientists’ expectations of how well they could survive at sea. On their way from Japan to the US, many found themselves trapped in the massive Pacific gyre.
The study’s researchers describe what surprised them when they examined the gyre:
“Our new observations in this gyre reveal that coastal species are not only present but are common on floating plastic debris, including objects that have been newly colonized at sea and are not from coastal sources, such as derelict fishing gear lost on the high seas. These observations, coupled with prior at sea records, reveal a picture of persistent coastal marine biodiversity on the high seas, sustained by plastic pollution and altering the long-held assumption that rafting coastal species reflected temporary ocean passage.”
The researchers introduced the word neopelagic to describe this newly identified community of species. The neopelagic community is made up of species that have historically traveled temporarily across oceans via such vehicles as surface bubbles or larger animals, and the emerging community of rafters—such as barnacle and mollusk species—who make their way aboard enduring plastics to live at sea on their hosts indefinitely.