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[Morty]

I've never heard this particular version of the erosion of genetic diversity RG, do you have a source for this?

As far as the 40% rate of by catch for T steelhead ....well the traditional harvest rate for IF coho through to the 80s was 60% to 70% (from Brian Riddell's talk at the BCWF selective fishery seminar earlier this year) and still the long term average return of fish was maintained.

Other research on T steelhead found there was a fry to parr bottleneck, regardless of the number fry produced we ended with the same # of parr implying there was some loss of productivity in the rearing waters.

Here's what Rodney wrote to another thread this September...

So when it comes to "fitness", big or strong does not always translate into "fit" if we are talking about genetic or adaptation. A population is not fit if there are only large fish, or only small fish, or medium sized fish. Fitness of a population can be measured by diversity. The more diverse a population is, the stronger it is when it comes to a change in environment, diseases, predation etc.

Killing that one big fish does not alter the fitness of the population, you're not taking away all the big fish immediately. If it was a female, then yes you're losing a lot of offsprings so that has an impact on the population.

If we are selectively harvesting only big fish (like we have unconsciously been doing) - directional selection, then that's bad for the population in the long run. You're shifting the bell curve of the population spectrum. Over time, fish become smaller because you're slowly taking out the genes that yield larger fish.

Selectively spawning only large fish at the hatchery is no good either, again, directional selection. This time, the bell curve of the population spectrum shifts right instead of left.

[RalphH]

In Darwinian terms 'fitness' means rearing the largest number of a cohort or generation to reproduce. Size doesn't matter. Pink salmon may be a good example. Small mature size almost to the extent of coming from a cookie cutter predominates with little varistion.

 However with all salmonids, the larger the fish, particularly but exclusively with females, the more potential reproductive potential, larger females produce more eggs though large males can both control and fertilize more females.

It seems to me more and more people are recognizing many of our salmon species, at least locally, are smaller than we have historically seen on average. It also seems to me that hatchery  specimens are significantly smaller than their wild counter parts which wasn't the case 10 or 20 years ago.

[RalphH]

If it’s killing them care to explain why the couple hundred broodstock caught steelhead throughout the province that are caught primarily on bait and held for months have a mortality rate of basically 0

simple - they cull the ones less likely to survive. Bleeders don't go into the holding tanks. The brood stock info has been recognized to have been biased in this manner for at least 20 years.

[avid angler]

simple - they cull the ones less likely to survive. Bleeders don't go into the holding tanks. The brood stock info has been recognized to have been biased in this manner for at least 20 years.

Man you don’t have damn clue. You think they murder wild steelhead if they aren’t going to make it? You are really something else. I literally spoke with the chilliwack hatchery staff to ask what their yearly losses were. He said in the past few seasons they lost one fish. It jumped out of the tank and sustained injuries and died a few days after the incident.

[RalphH]

So what... the bleeders etc are not taken to the hatchery and put into the tanks so they would experience little or no mortality.

The 2nd issue is like so many you rely on the best case survival rates to support your position but ignore cases such as trout taken on roe which have far worse outcomes - like 30 to 50% mortality.

[avid angler]

So what... the bleeders etc are not taken to the hatchery and put into the tanks so they would experience little or no mortality.

The 2nd issue is like so many you rely on the best case survival rates to support your position but ignore cases such as trout taken on roe which have far worse outcomes - like 30 to 50% mortality.

No one is catching bleeder steelhead. It’s so rare to see.
If you actually caught more then a handful a season like every other idiot you would know that. Yes bait caught rainbow trout have a high mortality when caught on bait. Especially when caught on gear targeting larger fish.

I honestly can’t wrap my head around you. You talk about sports fishing like it’s the devil itself and the reason for collapses far and wide. But then turn around and say that when nets were taking thousands of ifs a year that it wasn’t effecting overall returns. Your position on pretty well everything fishing related  is so my friend backwards and outright stupid that sometimes I swear your just trying to mess with people.

[avid angler]

Also Ralph your contradicting yourself again. You said they cull the fish that won’t make it, are they killing them or just not bringing them to the hatchery? Which is it?

[AaronWilde]

So what... the bleeders etc are not taken to the hatchery and put into the tanks so they would experience little or no mortality.

The 2nd issue is like so many you rely on the best case survival rates to support your position but ignore cases such as trout taken on roe which have far worse outcomes - like 30 to 50% mortality.

Apples to Oranges. You said Trout.. Steelhead is a totally different situation. Trout often taken in frog water with bait under a float or on bottom, where they have ample time to swallow it - obviously there will be high mortality there. Steelhead are taken almost exclusively in fast moving water where they very raraly swallow the bait - it's almost always in the mouth, where the mortality will be very similar to fly or gear fishing. You're such a pain to argue with all your bullsh skewered stats.

[RalphH]

Also Ralph your contradicting yourself again. You said they cull the fish that won’t make it, are they killing them or just not bringing them to the hatchery? Which is it?

Cull: verb; to select from a large quantity

I suggest you have a loom at: http://ospreysteelhead.org/archives/TheOspreyIssue43.pdf

pages 14 to 16

Bob Hooton on published data from the BC Steelhead Brood stock collection mortality data:

The  best  available  sets  of  hooking mortality  data  for  steelhead  were  collected  during  the  1980s  on  Vancouver Island.    Those  data  have  frequently been  quoted  out  of  context  and  misapplied  in  British  Columbia  and  else-where.

 Largely  ignored  in  subsequent interpretation  and  application  of  those results were the following:1.  The  brood  stock  collection  mortality figures were minimal because:a.  They  included  only  fish  retained  and delivered  to  a  holding  facility,  not  fish that  were  occasionally  released  at  the point  of  capture  because  they  were bleeding  from  hook  penetration  and  it was judged they stood a greater chance of  survival  in  the  wild  than  if  handled and  confined  in  artificial  environments associated with transport and holding.b. They did not include fish that died in holding more than 24 hours after being captured.c.  They  did  not  include  the  occasional mortally  hooked  hatchery  fish  harvested  (legally)  by  the  brood  stock  collection crew. d. The data fail to acknowledge the higher  standard  of  fish  handling  exhibited by  the  trained  fisheries  professionals involved relative to that expected from"average" anglers. 

you might also look for The Wild Steelhead Coalition publication Catch and Release Impacts on Wild Steelhead: What we know and what we don't know.

There you will find,  that at least in Washington State where they kept proper records brood stock mortality varied from 9% to 23% in some cases.

[RalphH]

Aaron why would we not include other sport fish species in the discussion? Lot's of trout, Bulls and salmon are caught fishing with roe. Most data I have seen suggest those species experience higher release mortality than steelhead.

[AaronWilde]

Aaron why would we not include other sport fish species in the discussion? Lot's of trout, Bulls and salmon are caught fishing with roe. Most data I have seen suggest those species experience higher release mortality than steelhead.

I'm not saying disclude them, but what studies? There are tons of Trout/Char caught in lakes and I see tons of deep hooking in lakes, but for river fisheries which is what we are really discussing here you won't see as much deep hooking/mortality I guarantee. Bait under bobber/on bottom around a fish that is trying to eat food and yeah, you'll kill a lot more. Were talking about Steelhead and Salmon here, which once again are in moving water where I see far less of that. Almost every fish I have caught with a bottom rig and a worm/roe in frog water/lake water has swallow the bait. Put a worm/roe on a float and drift it for a Steelhead though and almost every fish is in the mouth/lip. Apples to Oranges. What studies show high mortality? These studies probably include feeding Trout/Char caught in lakes/frog water, where a ton, if not the majority of the fishing is probably done!

If you have put in any real numbers, as others have noted, you should have seen this by now. I don't think I've ever deep hooked a Steelhead, mind you I've only put in a few seasons and under 50 fish total. I also don't exclusively use bait though, probably 1 or 1 out of 5 Steelhead I catch is with bait. Just as many bleed from my fly in the throat or a big lure hook.

[RalphH]

if you are not aware of those studies, many of which are getting towards 50 years old then maybe you should look. Most were done in streams and rivers.

A lot of people also still fish with bait in streams, sloughs and rivers where they catch and hook trout char and salmon.

You can find a summary in the  Hooton article for which I provided a link above:

Data  available  from  various  hooking mortality studies involving a variety of  species  throughout  North  America offer  instruction  for  local  situations.The  feature  common  to  almost  all  the applicable  hooking  mortality  investigations on salmonids is that the use of bait results in the highest incidence of hooks penetrating  critical  anatomical  areas(e.g.  gills,  esophagus,  heart).    That result has been described for coho, chinook,  Dolly  Varden,  Arctic  char,    summer and winter steelhead, resident rainbow  trout,  resident  and  anadromous cutthroat trout and  landlocked Atlantic salmon.    The  higher  the  incidence  of hooking in a critical area, the higher the mortality   rate.      Another   consistent observation  was  that,  when  all  three gear types (bait, artificial lure, fly) were examined,  the  mortality  rate  was  highest with bait, followed by lures, followed-by flies.  Baited hooks produced mortality  rates  that  were  three  to  nine  times higher  than  when  artificial  lures  were used.    Studies  where  flies  were  also examined   normally penetrated  only  the  periphery  of  the jaws or mouth.

[buck]

Having been involved with collecting steelhead brood stock at the Chilliwack Hatchery for 30 years mortality rates were extremely low.  During that time frame we handled approximately 2100 fish which were caught, handled and transported to the hatchery.  The number of bleeders were almost negligible.
All brood stock caught by anglers were transported  to the hatchery. None were released as you have suggested. Some deeply hooked fish (line cut and hook left in fish) survived. After about 1 or 2 weeks in holding we would find the hook lying in the holding pond. Overall mortalities were were about 4-5 percent annually with most occurring later in holding and just prior to spawning. There was no culling of fish for size or physical condition. They all went to holding.

[RalphH]

Thanks Buck. I am not suggesting anything other than people read the segments of the article by Bob Hooton I quoted above or read the entire article

Four to five percent is consistent with what he estimates for professional brood stock programs. Winter steelhead Catch and release using mortality indicate  somewhat higher rates but generally not out of line with good c&r management practice.

This is not always the case and more often not the case depending on the species of fish.

I'd also like to say this part of the discussion isn't about the Vedder Chilliwack, it's brood stock program or about banning roe or bait.

[Rodney]

After about 1 or 2 weeks in holding we would find the hook lying in the holding pond.

Thanks Buck, finally someone who I know worked closely in the program is able to provide solid information.

This part I find interesting. Any idea how that happens? Does the hook get passed through the system or just popped out from the mouth?

So 4~5% mortality, looking at 2 to 3 fish from the 70 broods collected per season. Any particular cause of death that stands out?