Fraser River sockeye salmon preparing to spawn in the Adams River near Salmon Arm.

Main salmon killer still elusive, inquiry told

Report flags trouble at sea for Fraser River sockeye

No single force stands out as the main culprit behind the die-off of millions of Fraser River sockeye salmon in recent years, according to findings tabled at the Cohen Commission.

A new report analyzing cumulative impacts on sockeye suggests the fish most likely died at sea, not in the Fraser itself or one of its tributaries.

It points to ocean conditions and climate change as two “likely” factors that may have contributed to the long-term stock decline, particularly as juvenile sockeye migrate out from the mouth of the river to Queen Charlotte Sound and beyond into the open Pacific.

“It is very likely that poor marine conditions during the coastal migration life stage in 2007 contributed to the poor returns observed in 2009,” the cumulative impacts report says.

It notes water temperatures were much cooler in 2008, and the better conditions for salmon may have been part of the reason for 2010’s surprisingly large run.

Climate change and ocean conditions may also play a role further out at sea, it says.

“Some important predators appear to be increasing in numbers and some prey are decreasing,” it notes, rating that as a “possible” contributor to declines.

The report was prepared by consultants ESSA Technologies Ltd. and lead author David Marmorek testified at the commission earlier this week.

His role was to distill the findings of a dozen other scientific reports conducted for the commission to probe separate potential threats to sockeye.

The report found no conclusion is possible on the impact of pathogens and diseases in the sockeye decline.

It cited widely diverging scientific opinions of the inquiry’s two researchers who studied the possible role of salmon farms.

They found diseases from the farms might play a role but completely disagreed in interpreting the actual evidence.

ESSA’s report did note they agreed sea lice, escaped Atlantic salmon and waste from the farms were all unlikely to play a significant role.

It’s also unlikely, the report found, that Lower Mainland land use or upriver factors ranging from logging and mining to agriculture or hydroelectric projects were primary drivers of the decline.

Similarly, pre-spawn mortality of returning sockeye caused by habitat changes or contaminants were unlikely factors.

There are plenty of unanswered questions that were beyond the scope of the commission’s technical reports and therefore weren’t considered by their teams of researchers, Marmorek noted.

Large releases of hatchery fish may compete with salmon for food or attract predators to the same area, he suggests.

That may also be a factor with pink salmon.

The report notes there’s evidence pink salmon from Alaska and Russia compete alongside Fraser sockeye in the North Pacific and could cause food shortages that hurt sockeye numbers in years with large numbers of pinks.

It also raises the question of whether the 2008 eruption of an Alaskan volcano naturally fertilized the ocean with ash and boosted food supplies, leading to the supercharged return of 30 million sockeye in 2010.

Marmorek calls for more research on various salmon stressors, particularly in the early ocean stage.

The Cohen inquiry is in its final days of hearings, with senior officials now taking the stand from the Department of Fisheries and Oceans.

A final report is due next year.

The judicial inquiry led by retired Judge Bruce Cohen was called by the federal government after less than 1.5 million sockeye returned in 2009, far fewer than the more than 10 million expected.

Just Posted

Yale man arrested after fleeing police in downtown Hope

Man arrested on three outstanding warrants after being caught in stolen van

Tractor exhaust pipe causes fire on Agassiz field

Agassiz fire crews were on scene around 1 p.m. Tuesday

Waterworks situation on table at Hope District meeting

Council to make decision on 753 Waterworks transfer tonight

Still no decision on cannabis stores in Kent following public hearing

Staff will be bringing the bylaws back to council to include new amendments for location

Rail group to bring plan to Abbotsford council

Group is calling for plans to run trains on rail line between Chilliwack and Surrey

VIDEO: Missing teens named as suspects in three northern B.C. killings

Kam McLeod and Bryer Schmegelsky are wanted in the deaths of Lucas Fowler, Chynna Deese, unknown man

Northern B.C. double homicide, suspicious death: A timeline of what we know

Two teens from Port Alberni are now wanted Canada-wide in connection to the three deaths

B.C. teacher suspended for professional misconduct

Grade 8 shop teacher admits to use of vulgar language and profanities toward students

B.C. wine industry legend Harry McWatters dies

Among his accomplishments, McWatters founded the province’s first estate winery, Sumac Ridge Estate

Provincial health body refuses to release full findings of cancer triage system audit

Information and Privacy Commissioner asked to review redactions

Southern resident killer whale died of blunt trauma, likely from ship

J34 was found more than two years ago near Sechelt, but the necropsy findings have now been released

B.C. rail crossing death highlights risks for people in wheelchairs: watchdog

Transportation Safety Board points to ‘persistent risks faced by persons using assistive devices’

B.C. teens wanted in double homicide, suspicious death spotted in Manitoba

Kam McLeod and Bryer Schmegelsky were thought to have been seen in the Gillam area

VIDEO: Young couple found dead in northern B.C. had been shot, police say

Chynna Noelle Deese of the U.S. and Lucas Robertson Fowler of Australia were found along Highway 97

Most Read