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)

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

(Pixabay)
‘Roadmap out of COVID-19’: Innovate BC’s program helping businesses recover

CEO Raghwa Gopal said the tech sector is here to help brick and mortar businesses

Penticton fire crews quickly put out a small blaze at a home on Duncan Ave. E Monday night. (Mike Biden photo)
UPDATE: House fire sends one to hospital

The fire at the Duncan Place home was cooking related

Toronto Public Health nurse Lalaine Agarin makes preparations at Toronto’s mass vaccination clinic, Jan. 17, 2021. THE CANADIAN PRESS/Frank Gunn
3 deaths, 234 new cases of COVID-19 in Interior Health over the weekend

One death connected to outbreak at Kamloops’ Royal Inland Hospital, where 20 patients and 28 staff have tested positive

Head Brewer Kody Rosentreter, owner Wes Greve and taproom manager Lisa Deleo celebrated North Basin Brewing’s grand opening Jan. 22 and 23, 2020. (Contributed)
Osoyoos’ first microbrewery celebrates grand opening

The brewery hopes to show that the Okanagan is more than just wine country

Rolling seven-day average of cases by B.C. health authority to Jan. 21. Fraser Health in purple, Vancouver Coastal red, Interior Health orange, Northern Health green and Vancouver Island blue. (B.C. Centre for Disease Control)
2nd COVID vaccine doses on hold as B.C. delivery delayed again

New COVID-19 cases slowing in Fraser Health region

A Vancouver Police Department patch is seen on an officer’s uniform as she makes a phone call. THE CANADIAN PRESS/Darryl Dyck
Vancouver man calls 911 to report his own stabbing, leading to arrest: police

Officers located the suspect a few blocks away. He was holding a bloody knife.

Kelowna seen from the top of Knox Mountain. (Phil McLachlan - Capital News file)
Homeownership unattainable for many Kelowna residents

Single-person and single-parent households often have limited options when it comes to housing

A Kelowna cannabis manufacturer has acquired another cannabis-based firm. (Black Press Media File)
Kelowna cannabis company acquires edibles manufacturer for $24.9 million

The Valens Company has acquired LYF Food Technologies

Vernon has agreed to a goose cull to control the over-populated invasive species making a muck of area parks and beaches. (Morning Star file photo)
Okanagan city pulls the trigger on goose cull

City asking neighbours to also help control over-population of geese

LaRae Richards loads an order for deliver via Uber Eats Wednesday afternoon at Red Onion Burgers in Mountlake Terrace on May 17, 2017. (Kevin Clark / The Herald)
Uber Eats comes to Kelowna

There are more than 60 businesses on the online delivery platform

FILE – Canadian Prime Minister Justin Trudeau delivers his opening remarks at a news conference outside Rideau cottage in Ottawa, Tuesday, January 19, 2021. THE CANADIAN PRESS/Adrian Wyld
Vaccine CEO ‘very, very clear’ that Canada’s contracts will be honoured: Trudeau

Trudeau says he spoke to Moderna CEO on the morning of Jan. 26

Vernon North Okanagan RCMP impounded a car after the driver was caught doing 113 km/hr in a 50 zone. (RCMP image)
Vernon car impounded after going 113km/hr in a 50km/hr zone

RCMP caught speeder near Village Green Mall at 5 a.m.

Most Read