Tagging experiment offers evidence that setnet-caught kings survive

A sockeye salmon’s tail protrudes above the edge of a bin on a setnet site July 11, 2016 near Kenai, Alaska. (Photo by Elizabeth Earl/Peninsula Clarion, file)

Editor's note: This article has been clarified that a king salmon did not gill in Brent Johnson's selective harvest module and to correct a misspelling that a setnet can be pulled in in the event of waves.

 

After the disastrous summer of 2012, when poor king salmon returns gave commercial Cook Inlet east side set gillnet fishermen only a handful of fishing days throughout the season, Brent Johnson began brainstorming.

A lifelong setnetter in the Clam Gulch area, Johnson knows he is allowed to harvest and sell king salmon under his commercial fishing permits, but he began thinking up ways to winnow out kings from the rest of the salmon. That way, he could release the kings alive and let them head up the river, contributing to escapement goals so the Alaska Department of Fish and Game could leave the setnet open, allowing him to still catch other kinds of salmon.

After a few seasons of testing experimental nets and tagging kings he released, he finally has some results to show, indicating that kings may survive being released from setnets.

His efforts started with designing a more selective net system. What he ended up designing included seine fishing net web intended for pink salmon, which differs slightly from setnet web. Stretched between two buoys, the goal was to corral the salmon into the net opening so the harvester could pull out the king salmon and release them while still harvesting other kinds of salmon. Calling it a Selective Harvest Module, he originally obtained the Alaska Department of Fish and Game’s blessing to test it at his site in 2014, but the web that year turned out to be too large and some salmon still gilled in the net, though no kings.

He got Fish and Game permits to test the nets in 2015 and 2016, but the crew was too busy fishing those years to test it — the device is designed to replace a single setnet but costs about seven times as much to build and weighs about 10 times as much.

“A setnet can be pulled in minutes if threatened by waves, logs or jellyfish,” he wrote in a letter to the editor submitted to the Clarion. “Not so a SHM!”

But that wasn’t the only king salmon conservation measure Johnson put in place on his site. In addition to cutting his net depth from 45 meshes deep to 29 meshes — common fishermen’s wisdom and some research says that king salmon tend to swim deeper in the water column than sockeye salmon — he also had his crew release any viable kings in the nets when they were picking a set. The goal was to get them to swim up the river and contribute to escapement so the commercial fishery managers wouldn’t have to restrict commercial fishing time.

However, other setnetters said those released kings were likely just being caught by other setnets closer to the mouths of rivers where the fish were headed. To answer that question, he approached the Fish and Game office in Soldotna to find out if he could start tagging some of the kings he released from his nets to see where they ended up.

He tagged kings in 2015 and 2016, but the 2015 tags probably came out because he later figured out he and his crew weren’t doing the tagging right. Because of improved returns in 2017, they kept the kings they caught — setnetters can sell their kings for between $3 and $5 per pound to a processors, meaning a 20-pound king can be worth between $60 and $100.

But four tags turned up this year anyway — in the oddest of places.

Two were turned in after being caught by commercial fishermen in Prince William Sound. Another was turned in from a fish caught near the Susitna River, though that tag hasn’t been verified as one of Johnson’s. And yet another was turned in by a sportfisherman from a king he caught near Big Eddy in the Kenai River.

“I thought (the tags on the fish caught in Prince William Sound) would turn out not to be my tags, but after we got pictures of the tags — they were mine!” Johnson wrote in an email.

Commercial fisheries area management biologist Pat Shields said the office didn’t fiscally support Johnson’s tagging project, nor was it a large enough sample of fish to be called a tagging study, but it was interesting that the fish survived being released from a setnet.

“We were not looking for tags, and it’s possible that others were not recovered,” he said. “It does lend credence to what people thought, that if you get a fish in a gillnet and it’s not gilled, that some of them can survive.”

Fish and Game doesn’t have the money right now to conduct a study of kings released from setnets or on whether shorter setnets catch fewer kings, Shields said. To design a study, researchers would have to include many more fish, more net sites, more times of day and control factors, among other considerations. There’s been research interest in it before, he said, but it’s been difficult to study.

Because Johnson’s tagging work was not part of an official study, the tagged fish were not genetically sampled upon harvest to determine what river they were from.

When a fish is captured, it can interrupt a normal return and spawning pattern, Shields said. That’s well known and Fish and Game’s scientific studies account for it, so in this case, the fish caught in the Susitna River area, Prince William Sound and the Kenai River don’t necessarily mean that was the stock those fish belonged to, he said.

The controversy over net depth affecting king salmon harvest is not a new one in the east side setnet fishery, but has come to a head since the disaster in 2012. Several fishermen, including Johnson, have advocated for setnetters to shorten their nets to reduce king salmon harvest. Closer to the mouth of the Kenai River, setnetter Gary Hollier was one of the first voices to advocate for the shorter nets, and estimated that since he did so, his nets have caught about 80 percent of the sockeye and 50 percent of the kings they used to. Like Johnson, he said his crew also releases the live kings and keeps the dead ones in an attempt to reach river escapement.

This year was a pleasant surprise for setnetters, with healthy returns of kings in both the early and late runs to the Kenai River.

“The king run actually bounced back a lot faster than I thought it would,” Hollier said.

Johnson said his crew’s data abound kings caught and released, which includes the time and net location where they were caught, wasn’t always perfect but the recovery of the tags gave him hope and he wanted Fish and Game to tag more kings caught in setnets.

“Our sample size is small, but there is a strong indication that released kings survive in significant numbers,” he said.

Reach Elizabeth Earl at elizabeth.earl@peninsulaclarion.com.

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