Hey everybody! As many of you know, I don’t just write for fun — I also make my living as a freelance science and travel writer. My latest feature story for EARTH magazine just went live: Setting Sail On Unknown Seas: The Past, Present and Future of Species Rafting Around the Globe.
On June 5, 2012, several thousand castaways rode a massive boxcar-sized dock to landfall on Oregon’s Agate Beach, just north of Newport. A plaque on the side, written in Japanese, revealed an unprecedented journey: The dock had been unmoored from the Japanese coastal city of Misawa during the catastrophic tsunami on March 11, 2011.
The dock and its inhabitants — as many as a hundred species, including mollusks, anemones, sponges, oysters, crabs, barnacles, worms, sea stars, mussels and sea urchins — spent more than a year at sea, drifting 8,000 kilometers across the Pacific Ocean. Within hours of the dock’s discovery, marine biologists from Oregon State University’s Hatfield Marine Science Center were on the scene, identifying species and raising red flags.
“Very quickly we realized we were dealing with a cast of very bad characters,” says John Chapman, an Oregon State University marine biologist who was among the first on the scene. And it was not a small cast: More than two tons of living organisms would eventually be removed from the 20-meter by 6-meter by 2-meter dock. “This was essentially an intact subtidal community of Asian species, aliens fully capable of reproducing, colonizing and invading the Oregon coast,” Chapman says.
The arrival of the dock and its species came as a shock: “Before June 5, 2012, we would have said it was impossible for something like this to happen,” Chapman says. “The notion of an intact coastal community surviving a year-long crossing of the Pacific is incredible.”
Of course, over geologic time, incredible journeys like this have occurred before: Primates rafted from Africa to South America, lemurs forded a 400-kilometer-wide channel from mainland Africa to Madagascar and plants colonized the farthest ice-free reaches of the Arctic. “On an evolutionary timescale, rafting has played a tremendously important role in the dispersal of organisms around the globe,” says Martin Thiel, an evolutionary biologist at the Catholic University of the North in Coquimbo, Chile.
But while long-distance rafting events have occurred throughout the history of life on Earth, the geologically recent advent of human settlement, culture and infrastructure is fundamentally changing the rafting game. “Rafting was once a rare phenomenon,” Thiel says. “Now it’s happening everywhere, all the time and we don’t yet know the consequences.”