If you go to the Chilliwack Progress web page there is some video they shot and edited.
Chris
Radio tagging a new angle for sockeye study
“Fish on!” yells the angler, as he hooks a sockeye and reels it in from a gravel bar in the Fraser River near Chilliwack.
He and other volunteer anglers are “bottom-bouncing” for science as part of the ongoing sockeye mortality study at Grassy Bar.
The fish is gently lifted out of the net, placed in a black mesh bag and walked along the shore to a large floating pen, where it will remain for 24 hours, before being assessed and released.
The numbers of both the sockeye and volunteer anglers are strong so far this year, says study coordinator Jim Thomas.
A whopping 63 sockeye were caught in one day last week, which he says is a sign the somewhat healthier summer run of Chilko sockeye had likely entered the river system.
“Monday was the biggest day we’ve seen in the two years of doing this,” Thomas tells The Progress.
“And even though there are huge concerns around the retention of sockeye, we’re clearly seeing a greater abundance right now in the river than we did at this time last year.”
This year marks the second year of the four-year study undertaken by Thomas, looking at the impacts of catch-and-release sport fishing on sockeye.
The $56,000 research study is funded by a grant from the Fraser Salmon and Watershed Program (FSWP), in conjunction with DFO. The goal is to catch 700 sockeye over the course of the multi-year study.
When The Progress news team arrives at Grassy Bar last Tuesday, sport fishers are lined along the shore, casting into the water, enjoying pleasant riverside conditions and the chance to fish despite a partial river closure in effect.
“This is a legitimate place to fish right now and not feel guilty, because you’re doing it for science,” says Fraser Valley Salmon Society rep Frank Kwak, who is assisting with the field work for the study.
He was busy that afternoon, helping to scoop and release the many pinks, jacks, chinook and sturgeon caught incidentally in the beach seine net.
“If I was going to go fishing this week, I’d be here,” he says.
In fact, the volunteer numbers have been “exceptional,” so far this year, says Thomas.
An average of 28 to 33 anglers per day have been shuttled by boat to Grassy Bar to participate in the short-term mortality study, he added.
It’s no wonder the numbers are strong. The anglers wouldn’t tality study, he added.
It’s no wonder the numbers are strong. The anglers wouldn’t otherwise be permitted to use that particular fishing method right now, given the low numbers of returning sockeye, and the specific DFO fishery notice asking anglers not to bottom bounce on that part of the Fraser for the sake of conservation.
But here at Grassy Bar, bottom bouncing, sometimes derogatorily referred to as “snagging” or “flossing,” is permitted this month only by DFO, to allow the study volunteers to provide data on the impacts of catch-and-release fishing on sockeye.
That’s what attracted angler Brian Forster and his family to participate in the study on the Fraser for the second year, while camping in the area near Harrison Bay.
“It’s great because even though the fishing (for sockeye) is closed, we still get a chance to come out here and fish,” he said.
The hotter temperatures seen earlier in the month have cooled down, and river temperatures were hovering at about 18 degrees last week, which is considered more conducive for the passing spawners.
At the study site, they’ve had a total of about 200 sockeye, bobbing at different times in the pens since they started the field work on Aug. 10.
“We’re actually ahead of target,” Thomas said.
“There’s only been one mortality so far out of about 150 fish,” he said.
Last year they saw two dead sockeye out of 173 study fish.
“So it’s corroborating the results from last year so far,” Thomas added.
The other significant aspect this summer is that it’s a pink year, and they’re seeing increased numbers of pink salmon as well, which might impact the “catch-ability” of the sockeye.
Carleton PhD student Mike Donaldson is responsible for the radio-tagging part of the study, which is a new addition this summer.
“We’re putting out between 75 and 100 tags (over three study periods), and the purpose is to track their movements upstream, and their behaviour after release, that’s the main objective,” Donaldson says. “It allows us to assign survival based on whether they make it up to the spawning areas.”
Three groups of fish are being tagged, and scientists will be tracking their movements with transmitter monitoring stations posted throughout the Fraser River watershed. They include the freshly landed fish from the volunteer anglers, the beach-seined fish, as well as the ones that have been penned for 24 hours.
On the same day at the study site, DFO biologist Jayme Hills is collecting blood and tissue samples, while Donaldson inserts the radio transmitter tags into live fish.
“I’ve taken samples from the heart, liver, muscle, gill, and brain,” Hills says.
She’s also collecting blood plasma and DNA samples to find out what sockeye stock the Fraser sockeye belonged to, and looking to see which stress indicators are present in the blood.
“We can look at a bunch of different things with five tissues, including everything from immune response to osmoregulation, to how prepared they were for fresh water.”
They’re sampling fish from in fresh water, as well as from the ocean to compare.
“The radio-tagging opens up a window onto a totally different world,” said Thomas.
The study is open to volunteer anglers of all experience levels. Check out
www.thinksalmon.com/fswp_project/item/fraser_sockeye_hook_and_release_mortality_study/ for the results from year one.
This is the final week of the sockeye study on the Fraser for this year.
jfeinberg@theprogress.co
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Topic: Fraser River sockeye salmon C&R study (Read 78093 times)