Salmon survival rates linked to timing of release.

[Aquaholic]

Anyone here involved with this, or can comment on the validity of it?

Changing salmon hatchery release practices can improve survival rates: B.C. study

More than five billion juvenile salmon are released from hatcheries into the North Pacific Ocean each year, with about six per cent coming from B.C. and Yukon.

vancouversun.com

 

[Bryan Allen]

This is not new- Quinsam, Qualicum and Robertson Creek hatcheries have been experimenting with different timing and release/size issues for at least 20 years. Things such as matching the releases with the zooplankton blooms, size of smolts/fry, and studying the homing in of predators, dogfish and seals , to the releases. Here is a early report on what the hatcheries were invesigating in the 80s https://waves-vagues.dfo-mpo.gc.ca/library-bibliotheque/40640887.pdf start at p29.

 

[Last_Call]

Anyone here involved with this, or can comment on the validity of it?

Changing salmon hatchery release practices can improve survival rates: B.C. study

More than five billion juvenile salmon are released from hatcheries into the North Pacific Ocean each year, with about six per cent coming from B.C. and Yukon.

vancouversun.com

Have a read of the Community Hatchery Interview Report at the link below for a detailed report on this hatchery effectiveness review:

Reports and Products - PSF Marine Science Program

Reports and products from the Hatchery Effectiveness Review project. As they become available, all report associated with this project will be posted and freely available from this page. Community Hatchery […]

www.marinescience.ca

Summary of the program can also be found here - https://www.marinescience.ca/hatchery-effectiveness/

Every year roughly 300 million fish are released from B.C. hatcheries to enhance dwindling stocks and sustain fisheries. Despite overwhelming investments of time and money, little has been done to fully review the effectiveness of salmonid enhancement and impact on wild populations in BC. The Hatchery Effectiveness Review is aimed at optimizing hatchery practices, improving the efficiency of enhancement strategies and ultimately contributing to a more sustainable future for wild salmon.

Hatchery vs Wild Salmon Survival​

Results to date from our Marine Science Program highlighted the poor survival of hatchery fish from Cowichan River Hatchery, which consistently survive at less than half the survival rates of wild fish from the same system. While hatcheries and enhancement techniques will likely continue to be a necessity for the sustainability of wild Pacific salmon, there is room for improvement. This is particularly important given the ongoing fisheries restrictions necessitated by the very poor status of some Chinook and Coho salmon stocks, as well as the push for more production of Chinook salmon to meet prey needs for endangered Southern Resident Killer Whales.

The primary components of the program include:

• Reviewing cutting-edge research and molecular tools to better understand and improve the survival of hatchery-reared salmon in the future;
• Evaluating hatchery release strategies used in past years and the resulting marine survival of hatchery-released salmon; and
• Studying the effectiveness of hatcheries and interactions with wild Pacific salmon populations across BC

See the 2021 and 2022 Hatchery Effectiveness Review newsletters for recent updates, and explore this slide deck presented at the 2022 Salish Sea Ecosystem Conference.