Many of the animals are coastal species that live on a small island halfway between California and Hawaii, thousands of miles from their natural habitats. Anemones, tiny marine bugs, mollusks, and crabs were discovered on 90% of the rubbish. Scientists are concerned that plastic may help invasive organisms spread.

Plastic particles measuring more than 5cm (2in) in diameter were collected from a circular pattern of ocean currents in the Pacific. Dr. Linsey Haram, the project’s lead researcher at the Smithsonian Environmental Research Centre, said: “Plastics are more permanent than many of the natural debris that you previously have seen in the open ocean. They’re creating a more permanent habitat in this area.”

Plastic pollution has contaminated at least five circular patterns of ocean currents on the planet. “All sorts of stuff ends up out there,” said Dr. Haram. “It’s not an island of plastic, but there’s definitely a large amount of plastic corralled there.” A large portion of the material is made up of microplastic, which is difficult to see with the human eye.