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[Grub]

According to big steel "all the hatchery steelhead should be killed so that they do not breed with wild stock"

Ive noticed that a large distiction has been made by some between hatchery and wild steelhead. Some seem to think that wild steehead are a far superior race to the lowly finless hatchery fish. Is there any evidence that suggests the hatchery fish pose any danger to "wild" fish?

From what I know the only thing unwild about hatchery steelhead is that they are hatched and partialy reared in hatcheries. Once the cliped fish are releaed they spend their marine life just as uncliped fish. They eat the same food, make the same migrations, and escape the same preditors as the so called "wild" fish. In other words steelhead with out adipose fins are just as fit or "wild" as fish with all their fins intact. Thus  hatchery raised fish should have the right to breed with the "wild" fish.

Would releasing a hatchery steelhead for the puropse of increaseing the brood stock be a mark agianst conservation?

[Grub]

oops  wrong forum please move to general dis

[Floater]

Hatchery steelhead are there for the puropse of increaseing the brood stock. Think of how much the wild numbers have grown ever since the hatchery program has been introduced.

[BwiBwi]

If just taking genetics into consideration there is a few things to keep in mind.

A systerm with 2 pair of fish in the wild only has 2 genetic combination. However in the hatchery it will be 4 combinations. Hatchery try to mix a number of fish egg and sperm to allow for high genetic variation. However, during hatching to smolts, hatchery has higher survival rate in comparison to wild. So only 500 pairs of fish is required to achieve a release rate of 1.5 million fish. But in the wild to achieve 1.5 million smolts you need thousands of pairs of fish.  This translate to higher genetic pool than that of hatchery.

So in an endangered system with still a healty number of parent genetic sample, it is ideal to let the wild build it's on population. However, if there is only a handful left in the system leaving them along to reproduce may not be the best choice.

[Sterling C]

Hatchery fish are not meant to augment the numbers of returning wild fish. In fact they do quite the opposite, as hatchery numbers increase wild numbers decrease. Why? Simple answer, hatchery fish are competing with wild fish for limited habitat and food. As for hatchery fish being inferior, I think it is reasonable to say that in a hatchery envioronment juveniles are protected from conditions which in the wild would normally kill off all but the most fit. When these returning hatchery fish return and spawn in the wild they are depositing the genes of fish which are not fit for survival out in the wild. In other words, these returning hatchery fish are not meant to be alive in the wild and are passing on their legacy to wild fish.

[Grub]

Is there any scientific evidence that suggests that hatchery raised steelhead cannont reproduce as well as wild fish under natural cercumstances?     

[BwiBwi]

Don't know. But personally I believe ( at least) the first generation hathery should grows as well as that of the wild. Mind you, they are from the 'fit' to survive wild stock.

[funpig]

I question this perception that allowing hatchery fish to spawn in the wild is detrimental to the wild stocks.

Recently, my brother-in-law and his friends spent a week camping and fishing the Harrison.  They caught and released so many wild coho but not one hatchery coho.  During their trip they met up with a fisheries officer and asked him about that.  The officer told them that most of the fish that they were catching probably were hatchery but didn't have their adipose clipped upon release because of lack of manpower and funds.  This would indicate to me that fisheries is not to concerned about hatchery fish (disguised as wild fish) enterring the ecosystem.

Furthermore, I believe that only wild stock are used to breed each new generation of hatcheries.  And I would also guess that fisheries officers would tend to take the more superior wild fish (bigger, stronger) for hatchery breeding which would only help to improve the overall genetic pool.  Isn't that what happened with the current Chinooks in the Vedder?

Finally, I would think that the number of hatchery mating pairs is quite small to the number of wild mating pairs, so the better early survival rate of hatcheries should not result in any significant overall dilution of the gene pool.

[No_way]

I don't see how it could be a dilution of the gene pool.  They are part of the same gene pool.  If they were fish from different systems then maybe, but hatchery and wild fish can't really be more than one generation separate, if that.  You can't have "populations" without many generations of separation.  In other words: hatchery and wild breeding pairs could be cousins.  That's how close the groups are.  I can't see how talk of "dilution" or other genetic dispersion can really float.

[Big Steel]

Well I believe that Biff and Bwi, already made the point, and it is quite simple!!  But there are some that don't believe that a species breeding with a relative can cause any harm. Bottom line, the hatchery was put there so that the fishermen could catch and keep steelhead, while leaving the wild fish, the native fish to the river alone.  I don't even know why there is a need for a debate on the topic.  I don't know every scientific piece of info on this subject, I am not a biologist.  All I did was state what I had been told while at the hatchery.  Why do you think that the vedder hatchery takes steelhead that have made it to the hatchery back down to the bottom of the river.   So that they may be caught!!.  Anyhow, I think that it would be good for Buck, a person that works at the hatchery to comment on the topic, as he is probably the only one qualified to do so.  I;m pretty sure that the hatchery has reasons, and evidence for not necessarily wanting hatchery fish to spawn with wild fish.

[newsman]

Google DR. Ernest Brannon and read his paper "The Salmon & Steelhead Hatchery Fish Controversy" I think that should answer all your questions.

[Old Black Dog]

Hatchery fish are not meant to augment the numbers of returning wild fish. In fact they do quite the opposite, as hatchery numbers increase wild numbers decrease. Why? Simple answer, hatchery fish are competing with wild fish for limited habitat and food. As for hatchery fish being inferior, I think it is reasonable to say that in a hatchery envioronment juveniles are protected from conditions which in the wild would normally kill off all but the most fit. When these returning hatchery fish return and spawn in the wild they are depositing the genes of fish which are not fit for survival out in the wild. In other words, these returning hatchery fish are not meant to be alive in the wild and are passing on their legacy to wild fish.
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This is as noted a personal thought and has nothing to do with facts.

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Google DR. Ernest Brannon and read his paper "The Salmon & Steelhead Hatchery Fish Controversy" I think that should answer all your questions

[redtide]

yea.....those wild coho we all released this year could very well have been hatchery fish. just not enough funds to clip them all. inch creek does this as well. hatchery fish do spawn with "wild fish" every year and who knows what this means to the genetic pool. 1 male has enough milt to fertilize 3 or 4 or 5 ripe females in a heatchery environment. those offspring are considered "cousins" biologically. if cousins and cousins in 4 years time return to spawn with each other you can see the genetic pool being diluted. thats one conclusion that can happen if the conditions are right so please don't spear me for this....

[Rodney]

The problem with having this discussion is that most people tend to assume the possible negative impacts of hatchery raised fish can be seen after a couple of generations. Most of the predicted problems, which are genetic related, cannot be identified in a decade or less. The evolution of a population is shown in a temporal (time) trend, not in comparisons of the physical attributes between hatchery and wild fish.

Wild fish are not more "superior" than hatchery raised fish. They are simply better because they are products of natural forces. Organisms that are selectively bred by human (yes, we conduct selective breeding on them. I doubt we already have a full understanding of sexual dimorphism of salmonids and can conclude that large males will always breed with large females, etc) are products used to match our demand and best interest.

The juvenile phase between the egg and fry stages is an important phase in the entire salmonid lifecycle. During this time in the rearing streams, weak fish are eliminated due to predation, inability to hunt as well as others, competition for space, etc. These factors are absent in a rearing pond where hatchery raised fish are pellet fed. By minimizing mortality rate and raising the fish to the smolt stage, some weak fish that shouldn't survive during the rearing stage are receiving a free ride. When these fish return to spawn, the "weak" alleles (kinds of genes) might be passed on, which may shift the genetic frequency of a population and weaken it.

For those with a genetic background. If a disease that only occurs in juvenile salmonids is the product of a recessive allele, then offsprings that are homozygous recessive would not survive past the juvenile stage in the wild, but would do perfectly fine with the aid of hatcheries. If there is a higher number of fish that are homozygous recessive return to spawn, then it might result in a higher juvenile mortality in the next generation due to higher number of homozygous recessive offsprings.

As mentioned earlier, the clear effect on the genetic components of a salmonid population cannot be seen in one generation, but can be identified by looking at the trend over ten, twenty, thirty generations. Well, by that time (40, 80, 120 years), it would be pretty hopeless if there is indeed a problem. That's why the issue of hatchery vs wild fish continues to emerge in the scientific community.

So why do we raise more salmon than steelhead in hatcheries? Pretty easy answer really - demand. The sportfishery for salmon is much more heavily participated than for steelhead.

From an angler's point of view, more fish is always better. From a biologist's point of view, that's not necessarily true. Some hatchery proponents tend to lack a good understanding of fishery biology and push for higher production of fish to satisfy their own self-interest. If a population has already reached carrying capacity, then no matter how much more hatchery raised fish you dump into it, the stock will still not revive itself. We should really focus our money and effort more on producing and enhancing spawning and rearing habitats that have been lost due to pollution, urbanization, development and logging.

[rln]

.

So why do we raise more salmon than steelhead in hatcheries? Pretty easy answer really - demand. The sportfishery for salmon is much more heavily participated than for steelhead.
 
 I would beg to differ that the reason we raise more salmon than steelhead is partly due to the fact MOE wants nothing to do with hatchery steelhead and DFO wants to provide retention fisheries province wise, just a difference of opinion.


From an angler's point of view, more fish is always better. From a biologist's point of view, that's not necessarily true. Some hatchery proponents tend to lack a good understanding of fishery biology and push for higher production of fish to satisfy their own self-interest. If a population has already reached carrying capacity, then no matter how much more hatchery raised fish you dump into it, the stock will still not revive itself. We should really focus our money and effort more on producing and enhancing spawning and rearing habitats that have been lost due to pollution, urbanization, development and logging.

Name a river system that is at carring capacity for steelhead anywhere in BC that is also being planted with hatchery steelhead.

 In today's world of mass urbanization, hatchery salmonids of all types are going to be needed in the future to provide any sort of sport fishing oppurtunity in the Lower Mainland and on Vancouver Island. Just look at the streams in the south half of BC that have the best returns of wild winter steelhead and you will see that they are the ones with hatcheries on them, the Stamp/Somas, Chehalis, Cowichan and Chillawack/Vedder. No where does it say you need to plant so many fish that you end up with massive returns, just enough to offer fishing oppurtunites where you are not fishing on the last 100-200 fish. Look at the return of steelhead to the Squamish system and how frightening small it is. Mamquam and Ashlu rivers has less than 100 each on most years now, The Upper Squamish has less than 200 and the now wiped out Cheakamus was the darling of the system with recent years having returns less than 200 steelhead some years. Your lucky to have 500 steelhead return in some of the more recent years to the entire system. With more than 20 years of catch and release, no bait, little habitat work done, there are less fish now than when it went catch and release. Lots of people fear hatchery fish because they look at what Washington state has done by planting the same strain of fish in almost all streams and without a doubt this is a poor idea but on the flip side there are a lot rivers in Washington state than are getting more than fishable numbers of steelhead in them right now and as post on a previous thread about what to do in the "off season" well there is no off season down there. Like it is mention earlier, go to  www.nwfishermen.org   and check out what Dr Ernest L. Brannon has to say.There are 6 parts to read but a lot of it makes commen sense.