A 200 tonne dock from Japan covered in living, breeding species came ashore in Newport, Oregon. It was traced as being from Misawa. Picture courtesy Oregon Parks and Recreation Department.
Visitors to the beaches are alerted to possible tsunami debris.
Oregon parks officers and volunteer groups help to clean the beaches in Oregon.
Volunteers in action at Yaquina Bay
Chris Havel of Oregon State Parks and Recreation inspects one of the coastal drop-off points for debris.
This water bottle inscribed with Japanese writing has washed across the Pacific.
Dr John Chapman
Invasion Ecologist Dr John Chapman stands among the frozen samples they took from the dock.
These Japanese seastars were discovered on the dock and have been found to eat many species on the sea floor, including each other.
Asian shore crab
The Asian shore crab (hemigrapsus sanguineus)is another of the invasive species scientists are concerned about.
Brown seaweed undaria pinnatifida is used for making miso soup. Picture courtesy of Oregon Parks and Recreation Department.
Cleaning the dock
Oregon Department of Fish and Wildlife crews scraped all remaining biological material off the dock by hand.
Picture courtesy of Oregon Parks and recreation Department.
Weed torches were used to sterilise the dock. Picture courtesy of Oregon Parks and Recreation Department.
Burying the remains.
The exotic plants and animals were coated in chlorine and buried to kill them. Picture courtesy of Oregon Parks and Recreation Department.
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