Invaders from Japan
Oregon scientists were keen to destroy invasive sea creatures from Japanese dock
U. S. scientists say the consequences of not destroying Asian sea life on a dock that floated from Japan could have been catastrophic for North American sea species.
SEATTLE— The 20- metrelong floating dock that washed up in central Oregon last week from last year’s tsunami in Japan was surprising enough. What stunned scientists who rushed to examine it was the cargo: about two tonnes of living sea creatures, some of which could devastate local sea life.
“There was a huge amount of stuff. They were very healthy, very reproductive. And included in the list of species that we could identify were some very, very bad characters that we really are afraid of having here — so yes, this really is a horrible thing,” said John Chapman of Oregon State University’s Hatfield Marine Science Center.
Aquatic invasions
The large concrete and Styrofoam pier washed off the coast of northern Japan during the March 2011 earthquake and subsequent tsunami, contained at least 30 species. Many were not native to the North American coast, said Chapman, an expert in aquatic biological invasions.
The discovery on a beach outside Newport, Ore., shocked scientists, he said, because they had never before seen a piece of ocean debris wash up with travelling wildlife from so far away.
Usually, debris washes ashore with the kind of barnacles and other sea life common to the deep sea, posing no threat to shoreline populations.
“When we walked up to that float on the shore and saw it covered with Japanese organisms, it was the first minute that anybody has really worried about introduced organisms with marine debris. It was like landing on the moon,” Chapman said.
“It took us some time to just sort of grasp the enormity of what this was. We didn’t think such a thing could happen. And there it was, on our beach.”
Shoreline communities along the West Coast, such as Los Angeles Harbor and San Francisco Bay, are always battling invasive species to one degree or another.
Sometimes they’re brought in on bilge water from cargo ships, though tightened restrictions in California are making headway on that problem.
Oz battles starfish
Australian officials have been battling the introduction of the Northern Pacific starfish, or Asterias amurensis, in Tasmania for years.
“If the Australians could push a button and kill them all, they would do it. They’d push on top of each other to do it,” Chapman said.
Among the species found on the pier were Northern Pacific star fish, shore crabs and brown algae.
“We saw those three things right away, and we thought, ‘ Oh, if none of these other characters on there mattered, we knew this was a totally bad crew. And we don’t want them,’ ” Chapman said.
Scientists called the Oregon Department of Fish and Wildlife and the Department of Parks and Recreation, which oversees the beaches, and told them they had an emergency on their hands.
“We had to say, ‘ Please kill this as fast as you can,’ ” Chapman said.
Within two days, workers were out on the dock, scraping as many of the animals away as possible and burying them eight feet under the sand on the beach. They then attacked the dock with blowtorches to try to kill what was left. The state is now accepting bids to remove the dock, which has attracted thousands of sightseers since its arrival June 5.
They can’t go fast enough for Chapman.
“When this thing first showed up, people were trying to figure out where it came from, and it had a plaque with Japanese characters, so they could tell exactly where it came from.
“But the biologists that were there didn’t need that,” he said.
“It was writ large on the float: This is from Japan.”