Simon Fraser University Study indicates decline of Skeena River sockeye much steeper than thought

John Crawford
08/21/2019

SFU-salmon-report-Aug-2019-1.jpg
[PHOTO:     SFU News -- Simon Fraser University]

The lead author of a new study on Skeena River salmon data says the results are a wake-up call for the province.

Michael Price, who is a PhD candidate at Simon Fraser University, was commenting on a report published this week in the journal "Conservation Letters", which reveals sockeye populations in the Skeena have declined much more steeply over the past century than previously thought.

Researchers drew on 100-year-old sources of salmon data, for the study carried out by SFU and Fisheries and Oceans Canada.

The research team used modern genetic tools to analyse a collection of fish scales that had been in storage for more than a century, revealing population patterns of decline that are far greater than previously recognized.

Sockeye-salmon-2.jpg
[FILE PHOTO]

The report says annual sockeye returns to the Skeena have dropped from about 1.8 million  to 469,000 during that period.

Fisheries scientists began collecting scales from sockeye salmon caught in commercial fisheries in 1912, and the collection continued until 1948.

The analyses reveal century-long declines that are much greater than those based on modern- era abundance data, which only extend back to 1960. Previous analysis suggested that only seven of 13 populations declined over the last five decades. The researchers’ new approach shifted baseline data to as far back as 1913.


SFU-salmon-report-Aug-2019-2.jpg
[PHOTO:     SFU News -- Simon Fraser University]

The study found that selective gill-netting for larger fish is one of the main reason for the declines among the various populations of Skeena sockeye, although other factors also likely contributed.  
 
The Skeena is Canada’s second largest salmon watershed. 

Fast Facts (from SFU News):

·       Researchers used a collection of fish scales that had been in storage for more than 100 years;

·       Wild Skeena sockeye populations have declined by 56-99 per cent over the last century;

·       These analyses reveal declines that are much greater than those based on modern era abundance data;

·       Populations of larger-bodied fish have declined the most in abundance, likely because of size-selective commercial fisheries;

·       This research will help inform status evaluations and rebuilding plan discussions for depleted populations.

Use of this Website assumes acceptance of Terms & Conditions and Privacy Policy
© 2019     All rights reserved
2018 Bell Media