A make pink salmon makes its way upstream to spawn. New research out of SFU suggests during healthy spawns of one species, competition among other dominate fish feeding on their eggs breaks down, allowing smaller fish to share in a critical, nutrient-rich food source. (Michael Penn file photo)

Abundance of one salmon species affects all others, B.C. study suggests

Feeding on other fishes eggs more critical to health survival than previously thought

A healthy spawning run from one salmon species may play an important role in the health of others, new research from Simon Fraser University suggests.

It’s widely understood when salmon returns are low, dominant fish from other species will push out all smaller competitors to feed on the eggs. But in a study published this week in the journal Ecosphere, researchers from SFU’s Salmon Watershed Lab found when returns are high, the dominant fish will still fill their bellies, but also make room for the younger ones to share in the nutrient-rich feast.

“What we found really interesting is that the competition broke down,” Colin Bailey, lead researcher and PhD candidate said. “Typically when you read about competition with stream fish, the larger fish hold their territory — the larger or more dominate species out-compete the smaller fish. In this case, where we placed a high but realistic number of eggs, the competition dissolved. Small fish gained access to a really really high-quality food source.”

READ MORE: Record-low returns continue for Fraser sockeye despite success of Big Bar passage

For the study, Abundance of salmon key to feeding ‘underdog’ stream fishes, Bailey and biological sciences professor Jonathan Moore added between six and 3,575 pink salmon eggs in different locations of the Keogh River on Vancouver Island.

Fish were captured and lightly anesthetized to have their stomachs flushed and examined. (The fish recovered in an in-stream container before their release back into the river.)

The team found young coho salmon, small steelhead trout and bottom-dwelling sculpins were able to access large deposits of pink salmon eggs despite other dominant fishes.

The results suggest one species’ spawning numbers impacts food resources for entire fish communities.

READ MORE: B.C.’s steelhead need our support: Fraser-Nicola MLA

Bailey is planning future research on the subject, including this study’s possible connection to his previous research looking at the impacts of pink salmon runs on juvenile steelhead. In that study he found higher runs of pink salmon in the fall coincided with an earlier out-migration of steelhead in the spring. He said it’s commonly accepted in the scientific field that younger fish have less chance of survival during out migration, but there may be more to it.

“If you go to sea smaller you may not have a good chance of surviving, but maybe all that energy you acquire from pink salmon eggs the previous fall compensates for that,” Bailey said.

If the results follow his reasoning, it could potentially influence fisheries management policy in such ways as limiting harvests of large salmon runs where steelhead are struggling.



quinn.bender@blackpress.ca

Fisheries and Oceans Canadasalmon stocksScience

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

The Kootenay Boundary Physician Association is sponsoring a pumpkin carving contest at KBRH. Photo: Submitted
‘Carve your hearts out’ at Kootenay Boundary Regional Hospital

Pumpkin carvings by KBRH staff will be on display Thursday and Friday in the hospital lobby

First responders at a crash scene near Rossland on Thursday, Oct. 22. Photo: Trail RCMP
First snow in West Kootenay causes vehicle collisions

The Trail and Greater District RCMP’s weekly brief contains details on collisions

There has been COVID-19 exposures at two elementary schools in District 42. (Image courtesy CDC)
Interior Health reports 24 additional COVID-19 cases

This includes three school exposures in Kelowna

Some amendments have been made to the bylaw since it passed first reading. File photo
Second public hearing set for Rossland chicken bylaw

Amended bylaw would now require electric fencing to be put around yards with chickens

Katrine Conroy has won for the fifth time in the Kootenay West riding. Photo: Submitted
Katrine Conroy ready to tackle challenges after election

Conroy won the Kootenay West riding for the fifth time

Provincial health officer Dr. Bonnie Henry arrives for briefing on the COVID-19 situation, B.C. legislature, Oct. 26, 2020 (B.C. government)
B.C. records 217 more COVID-19 cases, mask use urged

Infection spike continues, 21 senior facilities affected

Andrew Duncan was the Green candidate for Kootenay West. Photo: Submitted
A post-election message from Green Party candidate Andrew Duncan

Andrew Duncan was a Green Party candidate for Kootenay West in the provincial election.

A raccoon paid a visit to a Toronto Tim Hortons on Oct. 22, 2020. (shecallsmedrew/Twitter)
Who are you calling a trash panda? Raccoon takes a shift at Toronto Tim Hortons

Tim Hortons said animal control was called as soon they saw the surprise visitor

Join Black Press Media and Do Some Good

Pay it Forward program supports local businesses in their community giving

The duffel bags were found to contain 84 pounds of cocaine, valued at approximately $1.2 million and 198 pounds of methamphetamine, valued at approximately $960,000. Photo courtesy U.S. Customs and Border Protection.
2 men accused of fleeing border agents near U.S.-B.C. border with $2M in drugs

Cocaine and methamphetamine seized by U.S. law enforcement in remote Idaho area near Canadian border

Pixabay photo
‘Horrific’ abuse of volunteers, staff by parents must stop: Chilliwack soccer club

Parents have become abusive after being told COVID-19 rules, email says

FILE – The Queen of Alberni ferry leaves the Tsawwassen Ferry Terminal in Delta bound for Vancouver Island, Sunday, July 29, 2007. (CP PHOTO/Richard Lam) CANADA
Mechanical failure leaves nearly 200 passengers stranded on BC Ferries ship for hours

A tug arrived after dark to safely nudge the vessel into a berth so travellers could finally disembark

Ridge Meadows RCMP (Black Press)
Maple Ridge X-ray tech convicted of sexual assault dating back 30 years

Allen James Brooks is expected to be sentenced in January 2021

BC Liberal Leader Andrew Wilkinson leaves the stage after announcing he is stepping down as party leader, during a news conference in Burnaby, B.C., on Monday, October 26, 2020. THE CANADIAN PRESS/Darryl Dyck
Too rural, not enough diversity, soul searching needed, say BC Liberals

Elections BC says there are about 600,000 mail-in and absentee ballots across the province still to count

Most Read