New Approach To Salmon Hatchery Production

[IronNoggin]

On average two million young Chinook salmon are released each spring from the federally funded hatchery on the Cowichan River. Within six months, nearly all of them are dead.

Year after year, the mortality rate is staggering, with less than 1 per cent of the fish living to return as adults. The dismal results are thought to be similar at other B.C. hatcheries, which pump out about 20 million Chinook annually, hoping for a miracle."

...

"At the Omega Pacific Hatchery, near Port Alberni, Ms. Schmitt held her fish in net pens when she moved them to salt water. Because of that, she got to observe how they fared over the first few months in salt water. She saw the mortality rate on a daily basis, and realized that if she didn’t figure out why so many were dying, her hatchery would go out of business.

Over the years, she began to grow her Chinook more slowly, using colder water and less food, mimicking the conditions in nature. Her fish were smaller, and tougher. And she saw the survival rates shoot up to 5, 10, even 20 per cent or more."

http://m.theglobeandmail.com/news/n...a-new-approach/article2438652/?service=mobile

Damn GOOD Work Carol!

Let's hope The Dino can lose the blinders just long enough to test these amazing results in the real world!!

Cheers,
Nog

 

[reelfast]

the best survival rates were obtained in 'natural spawing channels' where the feed was reduced by 75%. this forced the smolt to forage and compete limiting survival to the fittest. unfortunately, hatcheries are all about big numbers of smolt raised and released. <1% return rates are the norm, not just in your backyard.

 

[IronNoggin]

... unfortunately, hatcheries are all about big numbers of smolt raised and released. <1% return rates are the norm, not just in your backyard.

That is quite true, for the CURRENT practices in the vast majority of hatcheries.
What Carol at Omega is doing comes much closer to imitating "natural" processes, and that is evidently reflected in their resultant survival rates.
Once this new approach has been proven, it may well result in the overall reduction of smolt numbers produced, with an actual increase of numbers returning. Win-Win all the way around methinks...

Cheers,
Nog

 

[NautiGirl]

looks like it might save some feed costs too.

 

[Theb55]

One wonders how reduced numbers, using incubator boxes to augment existing wild stocks would work out. This had been my idea for a long time.

 

[IronNoggin]

One wonders how reduced numbers, using incubator boxes to augment existing wild stocks would work out. This had been my idea for a long time.

Under the right conditions, incubation boxes can work very well. Only applicable where the available habitat is up to snuff. Did just that with a remote population of Arctic Char on the Yukon North Slope in the past, and with another system I can't discuss openly (as it was conducted behind the Dino's back some time ago... )

Cheers,
Nog

 

[Theb55]

IMHO Vancouver Island has many such rivers that were decimated years ago by appalling logging practices that have gradually rehabilitated themselves over themselves.