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[fisher man]

 If i'm a hatchery fish that survives and spawns do my fishlings become wild and is that the objective of the enhanchment projects. if so is it working as in are we getting more wild in the rivers ie; vedder

[silver ghost]

I'm no scientist but i'll give it my best shot.

Short form answer: yes and yes.

The progeny from the hatchery parents will be "wild" per se - as what defines wild fish is the presence of an adipose fin, which hatcheries clip off to make identifying them easier for anglers. But since the parents were hatchery, the new generation of "wild" fish aren't true "wild's" in my opinion.

The second part of your questions is a little more complicated....

The objective of enhancement programs is to "enhance". They provide retention opportunities for anglers while inflating the size of the run. Fish raised in a hatchery have a better chance of survival. Some might argue this. But they are fed until a certain size which allows them to hit the ground running so to speak. On the other hand, their wild cousins...out of say 100 5 will survive, but the hatchery brethren will have 20 out of 100 survive (just for illustrative purposes). So fewer wilds go out to sea than hatcheries, who by proxy have a
better chance of surviving to adult stage and returning...whatever happens to them in the ocean is unknown...but more hatchery fish will come back simply because of numbers. I think the hatcheries also give a healthy "cushion" to the wild stocks as hatcheries will be caught more often due simply to their larger returning numbers, therefore giving the wilds better chances to escape and spawn...less chance of hooking a wild and therefore these guys don't become pincushions - hence the "leave after bonking" rule.

Is it working? Yes and no. Are we getting "more" wild fish in the rivers? Well, it depends on what you consider wild   Personally I feel that no true "wild genes" exist, as hatcheries use artificial selection to pair up two wild mates, whereas they would have chosen the healthiest and strongest partner in the wild. Some will also say that hatchery fish are inbred - on the chilliwack river I doubt this is the case, as they use wild fish only for broodstock - the chances of the pairs being from the same parents are low. But on smaller systems most fish are inbred, as the hatcheries have to make the best of what their broodstock anglers bring them and often time it will be two hatchery fish mating together if that's all they get one year...the chances of them being related are higher....In any case, we are without a doubt getting more fish returning in the river. I would think that without a hatchery, the "wilds" numbers would be way down also. This is because since more hatchery fish return, more fish are spawning in the wild, period. Despite the fact anglers take out the hatcheries for retention, even though people think "you're supposed to because it maintains the genetic integrity of the run" - there are no real wild fish. many hatcheries spawn in the wild...I think most wilds are progeny only once removed from hatchery parents. Therefore without the hatchery fish, there would be a very small run of wilds fighting the odds to return as adults.


If you want real wild fish, go to the Thompson or Skeena...oh, actually.... don't go to the Thompson  

Hope this helps.

[bigblue]

I remember reading in Dec Hogans book regarding a study by Washington Department of Fish and Wildlife scientists about survival to adulthood of wild - wild, wild - hatchery and hatchery - hatchery combinations. The study was done for Kalama River steelhead and only wild - wild combinations produced off springs surviving to adulthood in a statistically meaningful sense.  A wild fish mating with a hatchery steelhead had a "zero" chance to produce an off spring which will survive to adulthood. This was based on 30 years of field research so it does makes us think about benefits of a hatchery program vs. protection of wild steelhead.  

[silver ghost]

hmm I'd be interested to look at that book, what's it called? It would be hard to look at DNA samples of the adult fish and determine the origin of their parents...and this would probably be the only way to do it as there would be no way to track a fisk from the alevin to adult stage over 4+ years

[bigblue]

The book is called Passion for Steelhead and written by Dec Hogan.
The study was mentioned in page 296.

[Sandman]

To add to what fishhunter has said, the hatchery fish are there for one purpose, to provide angling opportunities and to allow anglers to retain a fish.  They are NOT there to try to rebuild the wild populations (although it is hoped the decreased pressure from anglers on the wild fish will allow more to survive).  If hatchery fish  spawn, they will produce offspring with less genetic diversity, so they will serve to weaken the wild population's gene pool.  Anglers are encouraged to kill the harchery fish they catch.  The only reason to release a hatchery fish is to allow another angler the opportunity to catch and kill it.  I will release a hatchery fish in the canal, with the idea that the fish is bound to be caught again before it reaches the spawning grounds.  However, if I catch one above Allison canyon, I will kill it and take it home.

Some rivers have had attempts to rebuild a wild population using fish raised in hatcheries (Living Gene Bank), but these are smolts that are captured on their way out to sea and raised in hatcheries until adults, and then spawned and their offspring are released into the original donor stream.

[lovetofish]

To add to what fishhunter has said, the hatchery fish are there for one purpose, to provide angling opportunities and to allow anglers to retain a fish.  They are NOT there to try to rebuild the wild populations (although it is hoped the decreased pressure from anglers on the wild fish will allow more to survive).  If hatchery fish  spawn, they will produce offspring with less genetic diversity, so they will serve to weaken the wild population's gene pool.  Anglers are encouraged to kill the harchery fish they catch.  The only reason to release a hatchery fish is to allow another angler the opportunity to catch and kill it.  I will release a hatchery fish in the canal, with the idea that the fish is bound to be caught again before it reaches the spawning grounds.  However, if I catch one above Allison canyon, I will kill it and take it home.

Some rivers have had attempts to rebuild a wild population using fish raised in hatcheries (Living Gene Bank), but these are smolts that are captured on their way out to sea and raised in hatcheries until adults, and then spawned and their offspring are released into the original donor stream.

I disagree with this statement completely. When 2 wild fish mate and produce offspring, their genetics will be the same regardless if their offspring were hatchery clipped or not. I believe that the hatchery on the Chilliwack-Vedder uses wild stock for its hatchery production so although the pairing would not necessarily be the same as in the wild, the overall genetics will be. Raising a fish in a hatchery does not change the genetics of the fish. The phenotype may be different due to the environment, but the DNA does not change due to a hatchery environment. Two hatchery fish making it back to mate and produce the next generation have proven that they have what it takes and natural selection will make their offspring phenotypically the same as offspring of wild fish.

[fisher man]

Thanks  guys for replying. it helps out alot. I used to think that hatchery fish were used to produce more hatchery offspring. Luckily i met a nice fellow (tuber) on the river and we talked as he explianed to me how they use wild fish to take up to the hatchery. So in my mind the only difference is a clipped fin? When that fish survives and comes back to spawn, and those offspring don't have clipped fins (then they are wild). Are we not restocking wild fish?
So my guestion now is how are they genetically altered other than being raised in a friendlier environment.
Cheers

[Kenwee]

Interesting article:


http://www.msnbc.msn.com/id/45743468/ns/technology_and_science-science/#.Ty7NppiidLq

[silver ghost]

Fish are never genetically altered per se... what people mean is that on some systems where there is minimal spawning habitat - like the cap - the fish are pretty much 95% hatchery, so there is no diversity as the hatchery staff breed the fish year in year out and choose which ones to breed. This is done so many times that often they breed two fish from the same parents, as the hatchery releases have a better chance of returning back in adult stage thus increasing the chances that brothers and sisters make it back to the fish fence and theoretically that is done to their progeny over and over until the whole run are basically genetically identical...

[silver ghost]

Raising them in a hatchery doesn't alter them, but just think...from a younger age the fish are taught to feed on the surface, as that is where their food is (pellets) this is bad because the little fish will think this behavior is okay and hence become vulnerable to predators when they are released

[jeff]

Fish hunter your last post is an interesting thought, so how much does this behavior decrease survival chances do you think.

[Sandman]

I disagree with this statement completely. When 2 wild fish mate and produce offspring, their genetics will be the same regardless if their offspring were hatchery clipped or not. I believe that the hatchery on the Chilliwack-Vedder uses wild stock for its hatchery production so although the pairing would not necessarily be the same as in the wild, the overall genetics will be. Raising a fish in a hatchery does not change the genetics of the fish. The phenotype may be different due to the environment, but the DNA does not change due to a hatchery environment. Two hatchery fish making it back to mate and produce the next generation have proven that they have what it takes and natural selection will make their offspring phenotypically the same as offspring of wild fish.

The scenario is not when two wild fish (and by this we should mean truly "wild" fish, but what is that really any way) spawn, but when two hatchery raised fish (fish that are raised by human selection, not natural selection) spawn.  Fish that spawn in the wild, compete with each other for spawning habitat and a mate.  The biggest and baddest of the fish get the best redds and the best mate.  The weaker fish are forced to take less ideal redds (lower chance of their eggs successfully surviving to hatch), or perhaps don't mate at all and their genes are naturally selected out of the pool.  However, if a pair of wild fish are taken for brood stock and spawned, there is the possibility of a fish that, if left to spawn naturally, may not have been successful for a variety of reasons (smaller, not aggressive enough, etc), being given the opportunity to pass on those inferior genes to offspring who, because they are raised in the hatchery, are given a better chance to survive to smolt stage than if left naturally in the river environment.  When these possibly genetically inferior fish are released, natural selection will of course, select out the weakest of those offspring and only the fittest will return, and if they are left to spawn, they will pass those genes (those still possibly inferior genes) to their own offspring, especially if they are spawning with one of their own siblings (which is likely as the hatchery fish are more numerous and therefore stand a statistically better chance of returning to spawn).  The next generation of fish (still genetically inferior to the wild population) could, if they survive, then match up and spawn with a wild fish and mix those genes (weakening the wild fish's genes or strengthening the hatchery fish's genes, depending on if you are a cup is half full kind of guy).  What is worse, is that the offspring of the hatchery produced pair is then taken as a "wild" fish and used to create another generation of hatchery fish.  Now, while in a river like the Vedder with a large gene pool of wild fish to draw on, the genetic dilution would be low,  you can see that this spawning of the hatchery raised fish could still potentially weaken the wild fish's gene pool.

[Sandman]

In a river with a sustainable run of 2000 wild fish, the approximately 2000 fish returning the following year would be offspring from the some 600-800 pairs that spawned successfully (were not caught by anglers, bears, otters, etc., and were not out competed by other spawners).  In a hatchery enhanced river, the 2,000 returning hatchery fish would be the offspring of a few dozen brood pairs, representing a loss of genetic diversity.

[jetboatjim]

i was involved in hatchey steelhead programs for many years......its simple , take away the enhancement and they stop returning.

a good example would be the brunette and kanaka creek in the early 90's had upwards 300-400 fish....cut the program in the late 90's and 3 years later you get 6 fish back.

it just shows the hatchery band-aid is not the solution.