Fishing buoys, fuel drums and even a derelict squid boat were among the tons of debris that floated into Alaska waters after Japan’s 2011 devastating earthquake and tsunami.
An Oregon aquarium is about to open a display of the disaster’s living legacy on March 11.
Oregon Coast Aquarium assistant curator Evonne Mochon Collura introduced me to some well-traveled newcomers.
“They’re swimming comfortably among the kelp right now,” said Collura.
They looked right at home there. Just looking at them, they’re unusual looking. Not quite tropical, but pretty-looking fish and healthy looking.
“They each have a beautiful barred pattern on their bodies,” Collura said. “Tall vertical stripes that alternate silver and black.”
Fittingly, they’re called striped beakfish, also known as barred knifejaws. Then we move to the much larger “Open Sea” tank to look for some bigger arrivals – silver torpedoes with deeply forked yellow tails.
“You see?” said Collura. “There’s a smaller school of larger fish that is staying tight and close. Those are the yellowtail jacks.”
Aquarium staff rescued more than a dozen jacks and one beakfish from the hull of a derelict boat last April. The half-sunk wreck of a commercial fishing tender appeared to have drifted across the Pacific after 2011’s big earthquake and tsunami in Japan–and carried the live fish with it.
“We don’t know how old they are,” Collura said. “We don’t know how long they were in the hull. It’s possible they got washed into the boat hull when they were small.”
The second beakfish on display was pulled up in a crab pot near Port Orford two months before the drifting boat hull showed up off of Newport. That surprise, fishy discovery was initially held at Oregon State University’s Hatfield Marine Science Center before transfer to the nearby aquarium.
Mochon Collura says DNA testing positively identified the now-grown fish as native to East Asian waters. They probably survived by nibbling on sea life that grew inside the hulk and whatever else washed in.
The long-distance hitchhikers were kept in quarantine for six months before being judged safe and suitable to display. Aquarium visitor Nicole Chason of Portland was suitably amazed.
“Very surprised that they made their way all the way here,” said Chason. “I hope that they’re happy, (laughter) and they are being well treated as visitors.”
The 11 yellowtail jacks that came through the quarantine period were put on display in a large tank that also holds numerous sharks, which might not seem very nice. Mochon Collura said with a smile that the sharks are well fed by the aquarium staff to curb their appetite for the foreign fish.
Government agencies and marine biologists up and down the West Coast continue to watch out for more tsunami debris and hitchhikers.
John Chapman is an aquatic invasive species expert at Oregon State University. He says Pacific Northwest coastal waters are probably too cold for the fish the aquarium put on display to reproduce. But there are lots of other potential colonists that worry him.
“Yeah, there are real bad characters in that debris,” Chapman said.
— including sea stars, seaweeds and parasites that could displace native species.
Fortunately, the volume of suspected tsunami debris washing up on our shores has tailed off in past year. What’s left out there is getting harder to distinguish from all of the other trash in the ocean. Chapman says it appears we lucked out.
“We don’t have the final answer that we have dodged a bullet,” said Chapman. “We don’t know that yet for sure. But I think yeah, as a rough estimate maybe we did.”
The caveat is that it sometimes takes a long time for an invader to become established. So the marine scientists will keep looking. One of the main methods of surveillance is to lower metal or plastic discs in the water to see what grow on them.
National Oceanic and Atmospheric Administration Marine Debris Program Director Nancy Wallace said these discs are known as “fouling panels.” They generally sit out for 1-3 months before being hauled up and scrutinized for unwelcome critters and organisms. Wallace said hundreds of fouling panels have been deployed along the coast from California to Alaska.
In addition, trained observers are making periodic checks for sea life that is out of place on the undersides of coastal docks and pilings.
The Japanese government donated $3 million from 2014-17 to support debris dispersal modeling and coastal monitoring around the Pacific Rim.
“The government of Japan was unbelievably generous,” said Wallace in an interview with public radio.
Non-native fish were also found alive inside one previous tsunami debris wreck, which washed ashore in southwest Washington in 2013. Chapman recalled that five knifejaws were found in the live bait well of that fishing skiff. The aquarium in Seaside, OR put one of those knifejaws on public display late in 2013, while the others were euthanized.
