OLYMPIA – Two new types of commercial fishing gear tested by the Washington Department of Fish and Wildlife (WDFW) last year appear to give salmon a much better chance of survival after they are returned to the water than traditional gillnets.
In a series of test fisheries conducted in Puget Sound and Willapa Bay from June through December, WDFW found that only 55 percent of the chinook and coho salmon caught with a standard gillnet were still healthy enough to swim away from the boat after release.
By comparison, about 82 percent of the chinook and coho salmon released from a tangle net – a new type of gear recently introduced in British Columbia – still appeared healthy. Using another type of new gear, the "floating box trap," the survival rate at the time of release was virtually 100 percent.
If those findings are confirmed by additional testing this year, they could have significant implications for the future of state fisheries, said WDFW director Jeff Koenings.
"By necessity, fishing seasons have become more and more restrictive in recent years to protect depleted runs of wild salmon that often mix with abundant stocks," Koenings said. "If, however, we can improve survival rates for released fish, we may be able to allow more fishing opportunities on healthy stocks while also providing greater protection for specific runs that are in trouble."
The main problem with gillnets is that they often suffocate fish by compressing their gills or injure them as they struggle through the net, said Geraldine Vander Haegen, the WDFW fish biologist who is supervising the gear trials. During last year's test fisheries, one out of every two chinook and coho salmon caught with a gillnet died in the net or could not be revived to a condition where they were likely to survive.
Tangle nets, by comparison, are designed with a smaller, looser mesh to capture salmon by the head or teeth, allowing them to respire while in the net. Left to fish for the same amount of time, tangle nets used in the test fishery caught 407 salmon – about half as many chinook, but just as many coho salmon as the gillnet. Only one out of five salmon caught in the tangle net were in a condition where they could not be expected to survive if returned to the water.
The floating box trap, which captures salmon by funneling them into a small webbed chamber, had the highest survival rates of any gear but also caught the fewest fish. Tested only in Willapa Bay, the floating box trap caught a total of 36 salmon, nearly all of which 34 appeared healthy at the time of release.
"We plan to make some adjustments to the floating box trap to improve its catching efficiency, but there's no doubt that most of the fish released from the trap were in great shape," Vander Haegen said. "We'll have to see how we do with it this year."
At the four sites where test fisheries were conducted last year, WDFW contracted with experienced tribal and non-tribal fishers to handle the gear and determine the best time and place to fish. Salmon killed during the test fishery were either given to contracted fishers as compensation for their work, donated to food banks, or were sold to local fish buyers, with the proceeds used to support the project.
A report on last year's test fisheries involving the tangle net is posted on WDFW's website.
Starting next month, Vander Haegen will supervise a new series of gear trials in cooperation with area fishers on the lower Columbia River under a new $400,000 contract with the Northwest Power Planning Council. She also plans a second year of testing in southern Puget Sound and may conduct additional tests elsewhere in the Sound and in Willapa Bay depending on available funding.
Koenings said those tests have high priority at WDFW.
"These alternative gear types could be another step in the development of more selective fisheries," Koenings said. "In recent years, we have begun marking hatchery fish, restructuring fishing seasons and reconfiguring the use of both commercial and recreational gear. These new gear types hold real promise for allowing fishers to catch abundant stocks while protecting those runs that are in trouble."