TECH

Fish native to Japan found in Port Orford waters

Mark Floyd
Oregon State University

NEWPORT, Ore. – A team of scientists from Oregon State University and the Oregon Department of Fish and Wildlife is studying an unusual fish captured alive in a crab pot near Port Orford this week called a striped knifejaw that is native to Japan, as well as China and Korea.

The appearance in Oregon waters of the fish (Oplegnathus fasciatus), which is sometimes called a barred knifejaw or striped beakfish, may or may not be related to the Japanese tsunami of 2011, the researchers say, and it is premature to conclude that this non-native species may be established in Oregon waters.

But its appearance and survival certainly raises questions, according to OSU's John Chapman, an aquatic invasive species specialist at the university's Hatfield Marine Science Center in Newport.

"Some association with Japanese tsunami debris is a strong possibility, but we cannot rule out other options, such as the fish being carried over in ballast water of a ship or an aquarium fish being released locally," Chapman said. "But finding a second knifejaw nearly two years after the discovery of fish in a drifting Japanese boat certainly gets my attention."

In March 2013, five striped knifejaws were found alive in a boat near Long Beach, Washington, that had drifted over from Japan. Four of the fish were euthanized, but one was taken to the Seaside Aquarium, where it is still alive and well.

OSU marine ecologist Jessica Miller examined the four euthanized knifejaws from Washington in 2013, analyzing their otoliths, or ear bones, for clues to their origin.

"The young fish of these species are known to associate with drift and may be attracted to floating marine debris," Miller said. "Japanese tsunami marine debris continues to arrive on beaches in Oregon and Washington – and some debris from Japan washed up on the southern Oregon coast this month – so it is not inconceivable that the Port Orford fish was associated with Japanese marine debris.

"The species is also found in other parts of Asia and the northwest Hawaiian islands, so it is native to a broader range than just Japan," she added. "At this time, there is no evidence that they are successfully reproducing in Oregon."

Tom Calvanese, an Oregon State graduate student researcher working with Oregon Sea Grant on the start-up of a new OSU field station in Port Orford, worked with the fisherman to secure the exotic species. The fish is approximately 13 centimeters in length, and thus not a fully grown adult, and was captured in a crab pot between Port Orford and Cape Blanco - just off the Elk River in southern Oregon.

"We are fortunate to have this occur in a fishing community that is ocean-aware," Calvanese said. "The fisherman who caught the fish identified it as an exotic then transported it to shore alive, where the fish buyer was able to care for it. It was then brought to my attention, initiating a response from the scientific community that will result in an exciting learning opportunity for all.

"It appears to be in good shape and was swimming upright, though it had a small cut in its abdomen," Calvanese said. "I talked to Keith Chandler at the Seaside Aquarium who suggested feeding it razor clams, which it took readily."

Steven Rumrill, a biologist with the Oregon Department of Fish and Wildlife, is working with Calvanese and others to transport the fish to a quarantine facility at the Hatfield Marine Science Center, where it will be under the care of OSU aquatic veterinarian Tim Miller-Morgan of Oregon Sea Grant.

"It is important that the fish be held in quarantine until the wound is healed and for sufficient time to ensure that it is free from any pathogens or parasites that could pose a threat to our native fishes," Rumrill said.

Sam Chan, an OSU invasive species expert affiliated with Oregon Sea Grant and vice-chair of the Oregon Invasive Species Council, has seen striped knifejaws in Japan and estimates this fish may be 1-2 years old.

"Therefore, it is unlikely to have left Japan in the 2011 tsunami," Chan said, "but a boat could have been milling around Asian waters for the past 2-3 years and then picked up the fish and ridden the currents over. The big question is – are there more of these?"

Chan said Oregon Sea Grant – an OSU-based marine research, education and outreach program – would work with Oregon fishermen, crabbers and others to keep a lookout for additional striped knifejaws and other exotic species.

Calvanese posted a brief video of the fish on you-tube: http://youtu.be/XzA4NPXTYqg

Oregonians who believe they have spotted an invasive species are encouraged to report it at http://oregoninvasiveshotline.org, or call 1-866-INVADER.