Net pen coho

Stonedfish

Known Pluviophile
Forum Supporter
I like programs like these but is a 10-20% return rate possible nowadays? I don’t believe the south sound net pens get close to that number.
SF

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Is this essentially what they do in the south sound net pen operations? Will these fish residualize?

I believe that would be one of the goals though it isn’t stated, to provide resident coho angling opportunities.
SF
 
I am not sure of those return rates either. But when you consider the fact that most river smolts are not making it back into the salt it could be seen as an enhancement? So is this the way to make up for not having natural estuaries were these fish could thrive?
 
Is it reasonable to assume that the mature surviving fish would return to the vicinity of the net pens instead of heading up the Skagit to the hatchery of origin?
 
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Is it reasonable to assume that the mature surviving fish would return to the vicinity of the net pens instead of heading up the Skagit to the hatchery of origin?
 
It’s my understanding that the southern killer whales will eat coho and chum, but prefer chinook. I’m not sure 5 lb or less resident net pen coho are going to do much for them.
Maybe @adamcu280 or @Cabezon can chime in on whether these fish would be beneficial to whales or if it is just PR hype.
SF
 
It’s my understanding that the southern killer whales will eat coho and chum, but prefer chinook. I’m not sure 5 lb or less resident net pen coho are going to do much for them.
Maybe @adamcu280 or @Cabezon can chime in on whether these fish would be beneficial to whales or if it is just PR hype.
SF


I am kinda confused about if these are expected to be resident fish or not. They compared it to similar program in Greys Harbor and those are definitely not resident fish.

Either way I am definitely onboard with any programs that might add a few more coho to the mix.
 
I would be surprised if WDFW was just pulling the return rate number out of thin air, they have very good data on return rates from net pen programs because of the coded wire tag system. The “Return rate” they are talking about probably includes all the fish that are caught as well as those that actually make it back to the pens. Based on the number of south sound net pen tagged fish that I have caught in the north sound over the last few years, that return rate must be pretty high.
 
PSA did a release of blackmouth at Point Defiance this last year. They stay led in the pen something like a month before they were big enough to let go
 
It’s my understanding that the southern killer whales will eat coho and chum, but prefer chinook. I’m not sure 5 lb or less resident net pen coho are going to do much for them.
Maybe @adamcu280 or @Cabezon can chime in on whether these fish would be beneficial to whales or if it is just PR hype.
SF
Here's the latest on winter and summer prey of SRKW. I helped with the data collection that resulted in the 2010 summer prey paper.
 

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Adamcu280-
Thanks for the links to those papers; I had read them. I would think that the SRKW are targeting the Fraser stocks not much of mystery. The orca are large animals with a huge daily consumption need. It only makes sense that targeting large salmon is the most efficient way to meet their diet needs. I have attached a photo (courtesy of the Stanwood historic society) taken in the 1890s. Those Chinook are examples of the prey those orcas evolved with; a far cry from the typical PS hatchery Chinook today (summer caught typically 28.5 inches in length and maybe 10#). What the SRKW need is an increased biomass of prey of larger sized individuals.


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curt
 
I would be surprised if WDFW was just pulling the return rate number out of thin air, t
They do have very good data, so either they are pulling that return rate out of thin air or at least out of history when marine survival rates were many times greater than in recent years. That's one of the things that really bugs me about WDFW. They have the technical talent to give honest answers and be transparent to the public, but somebody there just can't resist making shit up and not think it damages the agency's credibility.
 
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