ASTORIA — A camera dropped 80 meters beneath the research vessel is telling a story that recreational and commercial fishermen have never been able to offer.
The lens not only spies an array of adult black rockfish scouring the rock formation for food, but it also captures images of young-of-the-year rockfish barely 5 inches long.
It’s a rockfish angler’s version of watching the scouting reports of what the end of the decade might look like during their summer forays off the coast for rockfish.
“We get to see these little fish, see what’s coming,” says Leif Rasmuson, an Oregon Department of Fish and Wildlife ocean researcher. “We’re getting a picture of the future.”
After decades of relying on recreational and commercial catches for information, state fish biologists have embarked on their first independent survey of the most common rockfish species, which represent the backbone of these offshore industries.
Biologists off the Oregon Coast on the research vessel Pacific Surveyor are using underwater cameras and sonar equipment to engage in the first fishery-independent survey of black, blue and deacon rockish — the three most important bottomfish species in Oregon’s offshore fisheries.
By not needing to rely on harvest data, fishery managers will have unbiased estimates of population abundance and biomass for these three heavily fished nearshore rockfish species. Information will benefit commercial and recreational fishermen and the coastal communities that rely on those industries.
“I think it’s going to be a big game-changer,” says Maggie Sommer, ODFW’s fish management section leader in the agency’s marine program out of Newport.
The last stock assessment for black rockfish on the Oregon Coast was in 2015. Survey data logged almost exclusively from sport and commercial landings created uncertainty, because it was based on what anglers could catch, not what was actually underwater.
“We hope this give us a better picture of the stock status and what hatch levels are sustainable,” Sommer says.
“This will be a comprehensive survey that gives us a picture uninfluenced by fisheries,” Sommer says.
The end result will be a clearer idea of what fishing pressure and bag limits likely mean to this deep-water fishery to sustain it over time, Sommer says.
That will be key in 2023 when state and federal agencies rewrite a new rockfish stock assessment that will govern allowable sport and commercial catches for the immediate future.
In recent years, the black rockfish bag limits have bounced around from as low as four fish a day to as many as seven a day. It’s considered a deal-maker for a recreational charter fleet that considers black rockfish its bread and butter.
The data won’t be crunched until the surveys are completed, Rasmuson says.
So far, though, the picture is mesmerizing.
Most anglers see a school of black rockfish off an undersea rock pile as little more than a cloud on their sonar systems. The underwater cameras reveal the complex web of age classes, from 5-inch rockfish to those beasty 20-inchers that can take decades to reach that size.
Visibility has been as low as 4 feet along the north coast, but Rasmuson expects cameras to capture images as much as 25 feet away along the south coast, which traditionally has better visibility.
The surveys will be done down to 80 meters, the deepest depth of the largest majority of these species.
The crew follows up that data with hook-and-line angling to sample for age composition and maturity, Rasmuson says. They use shrimp flies and herring jigs to catch myriad sizes of rockfish, he says
The survey is expected to cost about $310,000, paid for by a $250,000 grant from the Oregon Recreational and Enhancement fund paid by anglers, and another $60,000 from the state’s fund fueled by fees on commercial fish landings.
The Pacific Surveyor started two weeks ago around Astoria and will plod its way south toward the California border. It covers about 175 nautical miles, and the vessel could be south of Port Orford as soon as late August.
Reach Mail Tribune reporter Mark Freeman at 541-776-4470 or firstname.lastname@example.org. Follow him on Twitter at www.twitter.com/MTwriterFreeman.