To Many Salmon in the Sea

[Birdsnest]

I hope those chefs who declared the ocean can sustain enough salmon for everyone get the opportunity to see this article and study. More and more evidence that Alaska, Japan and Russia are doing far more than minimal damage to natural salmon stocks in the pacific. And I invite this thread to be about salmon farming because this is what it is about although the focus is on salmon ranching.




https://www.nceas.ucsb.edu/news/too-many-salmon-sea

 

[wildmanyeah]

I will offer my opinion both for and against this theory.

Arguments for

1. The steelhead community has long believed that russian pinks have been negatively impacting steelhead. Steelhead travel the furthest and share some of the same rearing areas as russian/alaskan pinks.
2. Some believe that we have a strong run of pinks on Odd years because there simply is just not enough food for an even year and they get out competed.
3. Some also believe that is why we have dominate years of sockeye, Sockeye also rear in lakes for 1-2 years so maybe it's more to do with the lakes capacity then the oceans but that does not explain why ocean survival has dropped from 10% down to 1-5%.

Arguments against

1. Humpback whale populations in the pacific northwest have been increasing at 5-10% a year. Humpback whales eat the same thing as salmon (krill and bait fish). If there really is not enough groceries left in the sea how come their population is increasing. Maybe they can out compete salmon? I do not know


Feel free to add for and against arguments!!

 

[searun]

The Russian one's probably carry a nerve agent? Who really knows what the ocean's carrying capacity really is. Lower Fraser Chinook (Harrison and Chilliwack) do not leave the BC coast - they are in decline over past few years - no Russian pinks here, so what explains that?

 

[cuttlefish]

I agree density-dependent effects are apparent.
I agree with the three recommendations as written into the Abstract.
I don't see any reference to ocean carrying capacity for salmon biomass as Searun mentions above in the paper. I also don't see any consideration of immature salmon biomass in the ocean as prey, only as predators. But given that, I also don't see any consideration of different salmon species having different diets and even the same species having a different diet at different periods during their ocean-life stage. I do believe, juvenile Chinook and coho have been observed to prey on juvenile pink and chum in the ocean.
Not really offering any for or against arguements at this time, just agreeing and offering observations.

 

[agentaqua]

Good points, cuttle - and you are correct.

There's also numerous life-history strategies for rainbows/steelheads - not all migrate long distances in the ocean. Same argument for river-type verses ocean-type Chinook. Seems there is also a negative pink/sockeye relationship wrt ocean growth and mortality.

Alaska seems to pump-out quite a few chum...

 

[wildmanyeah]

The Russian one's probably carry a nerve agent? Who really knows what the ocean's carrying capacity really is. Lower Fraser Chinook (Harrison and Chilliwack) do not leave the BC coast - they are in decline over past few years - no Russian pinks here, so what explains that?

Harrison Chinook and Cowichan Chinook both pretty much stay their whole lives in the Salish sea area. Cowichan stocks have recently been increasing while Harrison have been decreasing.

Most guides that fish in Vancouver/Nanaimo/Pender Bluffs area have reported seeing record levels of bait in these areas from their recent years. Both stocks have similar levels of predation in terms of seals and sports fishermen. Why did marine survival crash in the early 1990's?

 

[Dave]

Can you explain that graph a bit or cite the source? Are we talking numbers, %, adults, smolts ...?

 

[agentaqua]

https://onlinelibrary.wiley.com/doi/pdf/10.1046/j.1365-2419.2002.00192.x
https://www.tandfonline.com/doi/abs/10.1577/T04-034.1

 

[Dave]

aa, your above publications are not regarding chinook, but I'm not sure if you are responding to my question about the graphs, or not ..

 

[wildmanyeah]

Can you explain that graph a bit or cite the source? Are we talking numbers, %, adults, smolts ...?

*Figure 2. Trends in brood year marine survival rate to age 2 estimated from coded-wire-tag indicator stocks across BC. Note: marine survival rate scale (y-axis) is not consistent throughout figure panels. Incomplete brood-year data is depicted from 2011 to 2015, and is based on model estimates.*


See attached Dave, Its by the DFO Canadian Science Advisory Secretaria, So according to AA the numbers can't be trusted but its the best I can find. Looking on Watershed watch salmon societies website for data but it looks like the don't publish or gather data.

Maybe you can try to contact this guy he seems to be the leading trusted source according to AA recent post.

Stan Proboszcz

Stan Proboszcz is the science adviser for Watershed Watch Salmon Society, a charity in British Columbia. He has worked on conservation science and policy research for nearly 20 years.

 

[wildmanyeah]

Chilliwack Hatchery Chinook also stay in the same area but as you can see their survival rate is much higher. Its trend is closer to Harrison

 

[agentaqua]

aa, your above publications are not regarding chinook, but I'm not sure if you are responding to my question about the graphs, or not ..

Right on both accounts, Dave. I think WMY answered your question(s).

 

[Dave]

Interesting, but I still find the y-axis confusing. It's not surprising Chilliwack River Hatchery chinook (the fall whites) survivals are like Harrison, as they are the same stock.

Contact Stan ?... not likely.

 

[wildmanyeah]

Interesting, but I still find the y-axis confusing. It's not surprising Chilliwack River Hatchery chinook (the fall whites) survivals are like Harrison, as they are the same stock.

Contact Stan ?... not likely.

The Y axis is in % so .05 is 5% and it's the estimated Survival at age 2. It was gathered thew CWT. Chilliwack hatchery survival is actually higher than Harrison but it follows the same up and down treads.

This video sorta explained it, Contacting stan was a bit of a cheeky joke poking fun at the other post lol

 

[Whitebuck]

Chilliwack whites the last few years have been awesome returns. Vedder whites returns are almost what they were 15 years ago, when we were seeing almlst 80000 fish back.The Harrison whites get worse and worse. We were almost 200000 whites 10 yrs ago on the Harrison

Can anybody guess what the differance is with these 2 identical stocks.

 

[california]

Can anybody guess what the differance is with these 2 identical stocks.

Based on your post history I'm guessing FN netting?

 

[Dave]

Two differences I can see – Chilliwack fish have a better egg to fry survival rates due to the hatchery procedures and, Chilliwack fish are not subject to FN fishing. Any one who witnesses the carnage at Chehalis Beach will know what I’m talking about. I would also wonder if the productivity of places like Harrison Bay have changed recently.

 

[Whitebuck]

California...I take my holidays from Sept 1 till Nov 1 and am on both systems daily. As soon as they started netting the reds on the Harrison and at mountain bar the Fraser the numbers dropped rapidly. I’m sure we all remember the dozens of 20-40lbrs that were left below Kirby....I’m sure we all remember the wasted fish at mountain bar left each year.
California, any first hand experience or thoughts?

 

[wildmanyeah]

Whose pasture?

"On a three-three vote, the Alaska Board of Fisheries has allowed to move forward a plan to dump another 18 million or so pink salmon fry into the Port of Valdez every year to add to the approximately 700 million pink fry being poured into Prince William Sound every year."

" nonprofit company that has grown from a small hatchery that released 7.4 million pink salmon fry in 1981 to one that now releases about 230 million fry and growing. "

"The stocking was destined to explode. By the time the Alaska legislature voted to ban fish farming in 1990, the annual fry dump into the ocean topped 1 billion small fish per year."

In a peer-review study published last year in the Canadian Journal of Fisheries and Aquatic Sciences, the scientists concluded appearances can be deceiving:

“We estimate that the PWS hatchery program has increased the total catch by an average of 17 million fish, of which 8 million have been allocated to pay hatchery operating expenses,” they wrote. “We estimate that the maximum sustainable yield (MSY) of wild spawning fish in PWS has increased slightly (28 percent), while in regions of Alaska without pink salmon hatchery programs the MSY has tripled. Our results support the use of a precautionary approach to future large-scale stock enhancement efforts.”

“Thus, not only are wild fish and shellfish facing direct competition from 5 billion-plus hatchery salmon now released into the North Pacific each year, but the ocean’s productivity is declining from the nutrient mining inherent with these industrial-scale ocean ranching hatchery programs.”

https://craigmedred.news/2018/05/17/whose-pasture/

 

[fish brain]

To me ocean survival and feed supply seem to be the main issues. I know of two "old timers" both dead now who used to talk about fish returning to the Cowichan system. One who grew up in Cherry Point talked about not being able to sleep when the salmon came in due to the sound of fish jumping in the bay, She lived right on the ocean front. The other who lived near Four ways about a half km from the ocean would talk of knowing it was time to go fishing, when they could hear the fish jumping in the bay from the farm.Who in my lifetime (51 years) can say that?
Our oceans and rivers can support WAYYYY more fish. To me the question is why aren't they? Are they leaving the rivers in sufficient numbers?
Are they dying prematurely? Do they have enough to eat if they survive to the ocean? Why not?