Plastic debris in the oceans is accidentally transporting creatures across the globe, scientists have warned.
For the first time in recorded history, researchers have discovered that entire communities of coastal species have crossed thousands of miles of water floating on makeshift rafts.
Between 2012 and 2017, nearly 300 species of marine animals arrived alive in North America from Japan, having travelled on crates and other objects released into the Pacific after the Japanese earthquake and tsunami of 2011.
"I didn't think that most of these coastal organisms could survive at sea for long periods of time," said Greg Ruiz, marine biologist at the Smithsonian Environmental Research Center. "But in many ways they just haven't had much opportunity in the past. Now, plastic can combine with tsunami and storm events to create that opportunity on a large scale."
John Chapman, a marine scientist at Oregon State University, added: "This has turned out to be one of the biggest, unplanned natural experiments in marine biology, perhaps in history."
The 2011 tsunami swept millions of objects out to sea, from small pieces of plastic to entire fishing boats and even docks. Scientists began finding tsunami debris washing up in Hawaii and western North America in 2012, with living organisms still attached.
They detected 289 live species on debris originating from Japan.