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[ShaunO]

A very interesting article where researchers from Oregon State University and the Oregon Department of Fisheries and Wildlife assert that fish raised in a hatchery environment change on a genetic level from their wild counterparts, in just one generation .  I've always been reluctant to believe that a smolt reared in a hatchery could be any different than a smolt raised in an open stream, but it seems I am wrong about that.

http://www.eurekalert.org/pub_releases/2016-02/osu-des021216.php

[blueback]

Very interesting in terms of implications of potential change to hatchery programs. Here's a link to the paper:

http://www.nature.com/ncomms/2016/160217/ncomms10676/full/ncomms10676.html

[Dave]

Thanks for posting this.  I can't see many changes on the horizon for BC's steelhead hatchery program coming from this study, as efforts are made to stop hatchery fish from spawning together and spawning with wild fish. Of course they do but the only way to stop that would be to curtail the hatchery program altogether.  The Canucks have a better chance of winning the cup this year than that happening 

Already I'm hearing grumblings from anglers on the C-V, suggesting more hatchery fish should be produced ... I predict it won't be long before hatchery fish are used for brood stock on this system and wild C-V fish are a memory.

[Novabonker]

er.  The Canucks have a better chance of winning the cup this year than that happening

Oh Ye of little faith.... Chris will welcome you to the dark (blue) side

[Dave]

Oh Ye of little faith.... Chris will welcome you to the dark (blue) side

No faith is right!  I turned 66 on Sunday and am becoming more cynical yearly
I will always be a Canuck fan, no matter how bad they are, and will always advocate for wild steelhead, no matter how dismal their future may be.
We are really looking forward to our annual spring counts; the work Buck and I supervised this past summer at Centennial Channel hopefully will show improved numbers and the trend for spawner numbers at the outlet of Chilliwack Lake will give an indication of this years upper river wild population. 

Anyone here have an update on the number of wild fish in holding for the Chilliwack River hatchery program?  last I heard it was about 30 

[Novabonker]

Well Happy Birthday!

[Dave]

Thanks Bill Are there 66 candles there?

Back on topic, does anyone know how many fish have been tubed?

[buck]

  Dave, 31 females, 17 bucks.

[Dave]

Thanks Pete

[Novabonker]

Is there always that much of a gender difference in returns? Sorry for the hijack

[Dave]

If I recall broodstock anglers always had a hard time capturing enough wild males.  Buck might chime in here. The hatchery fish entered in the Wally Hall Memorial derby this year are at an approximate 3:1 ratio favoring females.
There was an interesting post recently showing released steelhead juveniles also had a higher percentage of females.

[shuswapsteve]

In respect to enumerating adult Pacific Salmon species like Sockeye, there can be sex ratio differences annually, between geographic areas and run-timing groups. Some areas can have close to 50:50 while others can be skewed 60:40 (males or females being more prominent) for males or females.  It is challenging to obtain a unbiased, representative sample to reflect the true sex ratio.  If surveys have poor spatial (space) and temporal (time) representation that could bias the sex ratio.  Ideally, ground surveys should be done at equal frequency intervals over time and cover the extent of spawning for a particular stream.  Seems like an easy thing to satisfy, but in reality it can be challenging. Fish behaviour, predators and environmental conditions are factors that play into this.
 
For instance, males typically die sooner than females and leave the system making them less recoverable for survey crews.  Secondly, extreme environmental conditions (water temperatures or water levels) can impact sex ratio.  For instance, female Sockeye can experience higher enroute mortality if migratory conditions in the Fraser are extreme. Thirdly, predators (specifically bears) on spawning grounds can remove salmon carcasses making them less available for crews to recover in order to determine sex ratio. If salmon abundances on a particular stream are low and there many bears are feeding during the day then it may not leave much for crews to count in order to determine sex ratio - especially if they are only visiting the stream once every 7 days. This may necessitate survey frequency to be even more often.

[RalphH]

efforts are made to stop hatchery fish from spawning together and spawning with wild fish. Of course they do but the only way to stop that would be to curtail the hatchery program altogether. 

I understand the Province no longer stocks fertile trout - just sterile fish. If only sterile steelhead smolts were released from hatcheries chances of wild and hatchery breeding interaction would be zero. Of course sterile hatchery steelhead could still compete with wild fish for food and resources.

[Dave]

I understand the Province no longer stocks fertile trout - just sterile fish. If only sterile steelhead smolts were released from hatcheries chances of wild and hatchery breeding interaction would be zero. Of course sterile hatchery steelhead could still compete with wild fish for food and resources.

Hmmm, not sure about what the FWFSBC stocks in lakes but you raise an interesting and thought provoking point regarding hatchery steelhead releases.  This technology of course costs more money but the long term implications, ie curtail the use of wild fish, use excess hatchery fish as brood stock makes a lot of sense, imo.  I'm looking for a negative impact  .... honestly can't see one just now.
The interaction of wild and hatchery fish on the C-V is pretty much a moot point as hatchery releases are mainly below the Vedder Bridge, an area not particularly well suited to rear wild juveniles, for so many reasons as I'm sure you know.

Good thoughts RalphH. I would like to hear you or others expand on this possibly ground breaking idea.

Edit.  Could sterile steelhead still return to their home river?  Need some experts to respond ...

[clarkii]

Hmmm, not sure about what the FWFSBC stocks in lakes but you raise an interesting and thought provoking point regarding hatchery steelhead releases.  This technology of course costs more money but the long term implications, ie curtail the use of wild fish, use excess hatchery fish as brood stock makes a lot of sense, imo.  I'm looking for a negative impact  .... honestly can't see one just now.
The interaction of wild and hatchery fish on the C-V is pretty much a moot point as hatchery releases are mainly below the Vedder Bridge, an area not particularly well suited to rear wild juveniles, for so many reasons as I'm sure you know.

Good thoughts RalphH. I would like to hear you or others expand on this possibly ground breaking idea.

Edit.  Could sterile steelhead still return to their home river?  Need some experts to respond ...

Males potentially would, assuming hey undergo false spawning characteristics as they are not hormonallay sterile, only functionally sterile.

Females however are hormonally and functionally sterile, and do not undergo false spawning.  As such I would think they have no incentive to migrate back upriver .

Saw something similar with 3n kokanee.  Caught a few (37) Presumably 4 year old males that had all the morphological changes associated with spawning and were in the shallows area of the lake, whilst the only female we got was a dirty chrome and in the deeper portion of our shallow set.