Fish passengers have been found off the Oregon coast in the wreckage of a boat that appears to be debris from the 2011 Japanese tsunami.
Scientists say 21 yellowtail jacks and one Asian striped knifejaw hitched a cross-Pacific ride in the bow of the boat found last week.
Fish washed up in debris could bring parasites and diseases to native species, but biologists say the latest fish pose little threat.
However, they were quarantined at the Oregon Coast Aquarium.
It's not the first time dislocated fish have been found in northwest US waters. Last month, a striped knifejaw turned up in a fisherman's crab trap off the Oregon coast. And in 2013 biologists found five striped knifejaws alive in a water-filled bait box on a 6m Japanese boat washed up in southwest Washington.
Except for one fish, the aquarium in Seaside agreed to quarantine and exhibit, the rest were euthanised to minimise the risk of introducing invasive species. The latest find was in a 9m section of what officials believe was a 15m commercial fishing boat.
When it was still offshore, it was decided the fish posed little threat to the Oregon coast ecosystem.
Still, scientists were taking no chances and not releasing the fish, said aquatic invasive species expert John Chapman.
Since the tsunami scientists have found about 300 marine species that have drifted to the Oregon shore inside or attached to debris, he added. AP