Fishing with Rod Discussion Forum
Fishing in British Columbia => General Discussion => Topic started by: Gooey on September 10, 2004, 01:13:50 PM
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I think that we need to restrict access to a lot of these sensative areas/fisheries....I thinks its crap, that a big tommy cod is 13 inches now-a-days. whats that weight, 1lb, my guess is its barely a snack for an adult...so why kill it.
the mentality: "I killed it because I wanted to eat it, they taste rather good, and to my knowledge a 13" tomcod is rather large" is at the route of the problem.
a 13 ling cod maybe large now a days cause people have this kill everything mentality. Seriously, how far did that tommy cod go in terms of a meal? What would that tommy cod be worth if left in the ocean to grow and reproduce as opposed to that snack?
I used to catch tommy cod that were 3-4 lbs! This is a classic example identical to the east coast OVERfishery!
IMHO, killing a 13 inch tommy cod is morally no different than keeping an undersized crab! Why do we as humans have to be legislated into doing the right thing (throwing those TINY fish back)?!?!
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Goey [edited - personal attack], better educate yourself first, pacific tomcod only grow to 12" most are 7 to 10" , a 13" one is big, they also have a short life cycle and only live to 5 years. there are alot of people who like to eat fish that do not always target big fish like salmon, for example many people fish for smelt? as well as yellow perch?, and I have also ate alot of pansize trout that where great eating. I suggest maybe you join greenpeace if dont believe in people fishing to catch fish for eating
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Gooey....... People have a right to retain fish caught legally and eat them cause they want to.
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You surprise me doc...I thought conservation was important to you regardless of species!
Lucky...edjucate yourself...I dont have a clue about how old a 13 inch tommy cod is or their max life (bet its more than 5 years tho). My guess is that your 13 inch tommy is not much more than a year old so it probably never spawned. You only find tiny ones because no one allows them to live past a year! PS luck smelts are a totally absurd comparison...considering there are millions of them available. Trout is even a bad example as many ponds are stocked, others have winter kill, either way those fish SHOULD be harvested.
And AHans, why do you think stating conservation corncerns is "stirring the pot"?
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everynight I have been dogfishing at ambleside in the past few months I have noticed people poaching crabs, and I mean everynight, I have called the hotline, but never seen a dfo show up there
Hey lucky,yea i know what you mean....next time instead of calling the dfo try calling "B.C wildlife conservation officers" They are more likely to show up than the dfo. Oh yea their number is >>>1-800--663-WILD(9453). <<
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Thanks to the moderators for not shutting the thread down...indeed I do think this is an important subject, there is a mentality among many fishers that needs to be addressed. I included my self in this generalization Ahans and Lucky.
I took more coho than I needed last year, none went to waste, some were given away etc. But wouldnt have been better to take what I need and leave the rest to spawn? Its something I am going to be more aware of this coho season.
We all need to be more responsible before its to late, regardless of fish species, etc. There used to be 3-4 lb tommy cod, there still would be if it were not for mankinds over fishing. Its an attitude we all need to address.
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Hey Gooey...recreational fishermen keeping fish legally caught for eating is their right as long as they keep within the limits prescribed by dfo. Sportsfishermen's impact on conservation is hardly a factor in saltwater fishing compared to the commercial guy's out there. We don't kill fish everyday. If a guy hooks a small fish and he wants to eat it what's the big deal. He is not breaking the law. There are guy's here who fish regularly on the peirs in west van. They know the regulations, retention limits, size etc. You have a problem.......contact the dfo or conservation dept and ask them to revise the limits, size, species you think in in danger of being extinct OK.
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This is again a sensitive issue that would seem to be a direct attack on the flossers. It is afterall an ethics and morals issue. So I will not be surprised there are opposition to Gooey's personal view.
Read between the lines.
Oh yeah...the clicking will come soon.
Nothing useful to add? ::) This is a discussion about people's personal choices regarding ground fish etc.
The discussion is centering on whether a recreational fisher keeping his legal limit is harming the fishery, or whether the effect is negligeable in comparison to other factors.
Max - stop second guessing everything all the time. Here's a unique idea: take things AS THEY ARE written, now how you'd like them to read :o
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Gooey
When i lived on a road that I thought the speed limit was too fast, i leaned hard on the city to change it, I didnt go yell and whine at the drivers doing the legal limit. Gooey If people are legally fishing be it Possesions or methods, say your opinion without behaving like a child and losing what ever point your were trying to make. Even when I agree with your point, your annoying methods lose me. >:(
Personnaly i thought Tommy cods maxed out at about 1lbs
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The ones gooey caught musta been on steroids :D
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ignoring catch limits is more destructive than say keeping a tommy cod at 13inches length. one of rodney's reports actually state people used to take home 50 or more tommy cod per day. do a little math and you can see the enormous impact this can have on a species. people fishing legally and keeping their limits then trying to blame people that they should be selecting their harvest is just a non starter.
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You surprise me doc...I thought conservation was important to you regardless of species!
Lucky...edjucate yourself...I dont have a clue about how old a 13 inch tommy cod is or their max life (bet its more than 5 years tho). My guess is that your 13 inch tommy is not much more than a year old so it probably never spawned. You only find tiny ones because no one allows them to live past a year! PS luck smelts are a totally absurd comparison...considering there are millions of them available. Trout is even a bad example as many ponds are stocked, others have winter kill, either way those fish SHOULD be harvested.
And AHans, why do you think stating conservation corncerns is "stirring the pot"?
i totally agree with conservation and the need to address fishing practices.
but gooey....
you still haven't learned your lesson. just like 'the other' site, you go 'kamakaze' without taking the time to look at all the facts....
tommy cods are the smallest of their species. maximum length is 12 inches. 4 lbs is worthy of a nomination and registration for the national record.
ponds and lakes are stocked because of the depletion of the wild stocks. winter kills and other forms of extermination is used to balance the two. it was however, originally intended to control ferrel species.
when i was a boy, i remember seeing millions of smelts along the stanley park seawall, during their yearly migration. now due to over fishing, you'd be lucky to see hundreds.
there is no such thing as absurd, when referring to conservation. no species is immune to extinction.
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you must be thinking of greenling cod, or perhaps rock cod, do the research gooey before you spout off, type pacific tomcod on google , and educate yourself a bit
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Yes this is most likely a confusion about what is a "tommy cod". When I was a kid we all called kelp greenling (hexagrammos decagrammus) "tommy cod". The maximum size for those is, as Gooey suggests, more like 20+ inches and 3 or 4 pounds.
The pacific tomcod (microgadus proximus) is totally different and its maximum size is around 12 inches. It looks more like a hake or pollock.
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lucky, who's the one spouting off? The tommy cod I caught as a child were huge in comparison to what you are talking about. I lived in Cobble Hill (between victoria and nanimo) and I used to spend 5 out of 7 days down at the docs all thru elementary school. The fishing pressure wasnt huge in Cowichan bay and the tommy's GREW big. The were no greenlings til you got out in a boat around separation point and down a channel there. The biggest yellow eye and red snappers were in the 12lb range.
Yes that was 2+ decades ago but the point is that if a stock doesnt get over fished then it will be able to produce those larger fish!
And lucki you still haven't answered the question: where does a greater value lie in a 13 inch tommy cod...as table fair or left to grow and reproduce?
You know my answer and I am still waiting to here yours!
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In Gooey's defense, it is true about the loss of trophy sized fish from years past.
The prime example is the TYEE. 25 years ago they were classified as Chinook weighing 50 lbs or more. The decline, is definitely a result of over fishing. :'(
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I have seen numerous changes in fish stocks since I was a kid. As BlaydRnr has pointed out, there were tons of smelts available on local beaches to be caught. I've seen 100-150 lbs caught in one evening. Nowadays if you catch 20 lbs you be laughing. The beaches off the Maritime Museum used to have a huge oyster bed. That is all gone.
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I have never seen them Tomcod over a foot myself and from what I can see on the internet they never get more than about 12 or 13 inches. Check out the following link.
http://www.enature.com/fieldguide/showSpeciesSH.asp?curGroupID=3&shapeID=995&curPageNum=9&recnum=FI0070
Maybe those fish in the 4 pound fish were something else?
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The prime example is the TYEE. 25 years ago they were classified as Chinook weighing 50 lbs or more. The decline, is definitely a result of over fishing. :'(
That's kind of hard to prove.
For salmon, I would think that the decline in total population size could be caused by overfishing (along with habitat destruction - let's not forget about that). But the percentage of springs that reach a given size should remain the same, unless something is applying very strong selection pressure and affecting the genetics. Sounds like a good thesis topic. :) I should go back to school so I could go fishing for a few years. ;D
Long lived fish that spawn multiple times, on the other hand, are a different story. Species such as lingcod, rockfish and herring are being harvested when they've barely reached sexual maturity. So it's true that they never get a chance to grow big.
Gooey, maybe when you say greenling you are now talking about juvenile lingcod (ophiodon elongatus) which sometimes have green flesh?
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I have caught many a species of fish both as a sports and commercial fisher. Altho it was a looooooooooong time ago what I remember as a tommy cod looked much different than the one pictured in gmans link.
I have caught all sorts of benthic fish species and the fish pictured was definitely not what i was remembering. I had just moved to the island from back east so I picked up on what ever the locals shared...maybe I picked up an incorrect name...the bottom line is this thread is really about over fishing and the current mentality to harvest anything that comes to shore (legal or not depending who you are).
Simply put I wont kill a jack that wont provide my family with enough food for a meal. If you catch 20lbs of smelt...fly at 'er thats a lot of protien. But back to the question stated...whats one tiny fish worth in terms of a food source in comparison to being left to grow and reproduce?
It all comes down to that harvest mentality that, IMHO, we all need to be in more control of.
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The prime example is the TYEE. 25 years ago they were classified as Chinook weighing 50 lbs or more. The decline, is definitely a result of over fishing. :'(
That's kind of hard to prove.
For salmon, I would think that the decline in total population size could be caused by overfishing (along with habitat destruction - let's not forget about that). But the percentage of springs that reach a given size should remain the same, unless something is applying very strong selection pressure and affecting the genetics. Sounds like a good thesis topic. :) I should go back to school so I could go fishing for a few years. ;D
Long lived fish that spawn multiple times, on the other hand, are a different story. Species such as lingcod, rockfish and herring are being harvested when they've barely reached sexual maturity. So it's true that they never get a chance to grow big.
Gooey, maybe when you say greenling you are now talking about juvenile lingcod (ophiodon elongatus) which sometimes have green flesh?
of course habitat destruction is a contributer to the problem, but you can't dispute over fishing. if so, why is it still common to find white spring (ie.. the vedder) weighing in at over 40-50 lbs, but hard pressed to find red spring weighing in at least 35 lbs (anywhere in and around the lower mainland). you know why?... because trophy red springs are alot more desirable.
if the biggest and strongest fish is always targetted and killed, doesn't that alone, alter the 'make up' of genetics.
in the wild, it's the weakest and most vulnerable that's targetted. also, only the strongest and most fittest males are allowed to mate. therefore, if you wipe out the biggest and strongest fish, what do you think you're left with?
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Yes, you're right. I suppose with the salmon's short life cycle, in a few decades it might be possible to breed out most of the big ones.
I've always wondered if we're breeding deep running, long skinny salmon, and those that arrive early or late in the season, with our commercial fleets. We could easily be doing the same sort of thing to springs if people are releasing only small and/or white springs. I'd sure like to see some real research on the subject.
Is it possible to target large reds without catching small springs or white springs?
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BTW, I also think we may be selectively breeding less aggressive fish. The aggressive ones take a hook - BONK. The shy fish, swims up and get's lucky. We're weeding out the ones that bite :o
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Is it possible to target large reds without catching small springs or white springs?
yes...
on the most part, red springs migrate before the whites. also, larger reds have a greater advantage over the juveniles, therefore, they get to the bait first.
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Simply put I wont kill a jack that wont provide my family with enough food for a meal. If you catch 20lbs of smelt...fly at 'er thats a lot of protien. But back to the question stated...whats one tiny fish worth in terms of a food source in comparison to being left to grow and reproduce?
It all comes down to that harvest mentality that, IMHO, we all need to be in more control of.
Gooey.....if you really support the cycle of reproduction......you should ask yourself why you are fishing for salmon at all. We all know that salmon season starts when these fish come down for the purpose of spawning. Why not leave a "BIG" one alone cuz it's ready to spawn? I'm sure you've caught nice size doe's and bonked them throughout your fishing years. Also keep the roe for bait.
Now i ask you.....what's one "BIG" size Doe worth in terms of a food source in comparison to being left alone to spawn?
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Anybody see that commercial that was being aired for a short period of time talking about releasing the "big" one?
The guy stated that a larger chinook can carry 5000 eggs as opposed to a regular nice sized 3000 eggs.
The reasons for allowing the big one go to spawn were:
- Bigger fish, bigger fish genes
- Bigger fish, more eggs = more big fish
And...I don't remember the rest.
Anybody else see it?
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in response to fishing addict...salmon is a different situation than any other becuase they die after spawning (unlike steelhead or even tommy cod that may live to produce several generations of offspring).
Add into the mix that hatchery coho's (the only one we can kill) are meant to be harvested and really there isnt a reason not to take a hatchery salmon. In terms of salmon and steelhead, I wont take a fish if I think it will make a difference to the run (in 17 years of fishing the north shore I have never killed a seymour steelie). On top of that I was told by a reputable source that it only takes 4 generations for negative genes to really start been seen in a run of primarily hatchery fish. So infact it is good to take the hatcheries out.
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Both Gooey and FishiN AddicT brought up some excellent points. I've stopped fishing for groundfish eight years ago (actually, never really did that much, maybe once a year) after recognizing their regeneration time is simply too long.
Gooey's point regarding hatchery fish is good, but what about the big Fraser chinook and those big wild fish you see up north? By selecting the big specimen over the small ones when retaining fish, wouldn't it skew the gene pool? Same goes with groundfish (at least for pacific rockfish species). It is recommended to harvest smaller fish as fecundity of bigger fish is much bigger. Can't say much about the pacific cod species yet, will have to do some reading and get back on that later.
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Gooey,
Not all hatchery salmon are meant to be harvested. Hatchery salmon in many cases are released to shore up the population decline. The ratio between 'hatchery salmon' and 'wild salmon' are carefully being monitor as an indicator of success of the initiative. The result of natural spawning of hatchery fish are then consider wild.
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in response to fishing addict...salmon is a different situation than any other becuase they die after spawning (unlike steelhead or even tommy cod that may live to produce several generations of offspring).
that's true......but the key word is "after" spawning. I was merely pointing out the fact of bonking one that hasn't even had a chance to release their eggs. So really, the salmon dies before it had a chance to spawn.
My point is you're quick on the gun to shoot others' methods of fishing, size of fish, etc. etc. , but what make's you different? No rules or regulations has been broken.
The bottom line is there's nothing wrong with wanting to bonk a small fish compared to a big one (whether it's a tommy cod, Jack, trout, etc.) to eat at the dinner table, as long as the regs are followed. Some may find the smaller fish more tasty?
Plus......I always thought that size didn't matter? :o ;D ::)
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i remember we used to catch some true cod called "grey cod". some were caught while jigging with buzz bombs quite deep.they had very flakey white meat and were quite good. this was near sechelt about 10 years ago...maybe gooey was talking about these fish. they easily averaged 3-5lbs. havent caught any since though!
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I don't know if anyone here has heard the name Al Lill, he is a family friend, he's the one I referranced. Currently he has come out of retirement from the DFO I believe and most recently has been been the project consultant for the Greater Georgia Basin Steelhead Recovery Action Plan. He was the one the I spoke to regarding hatchery genes in the gene pool etc.
I took some genetics coarse (3rd year) and have a biology background too....any how, he an I had a relatively indepth conversation on this topic. At one point I firmly believe that if you take 2 hatcheries and they spawn naturally, then the offspring are as good as wild ; afterall the offspring had to endure all the pressures of natural selection .
Thats not the case. Weak genes from that initial hatchery brood will remian in the population and as Al pointed out to me, within 3-4 generations, those genes can really start to hurt the gene pool.
Just going back to grade 11 bio and the punnett square, one can see that negative (recessive) genes can hide in the gene pool in a heterozygous allele (search the terms on google if you want to understand a little more).
Bottom line is that there are very few rivers I am aware of that the main goal is to make sure that run doesnt die out. I think most hatcheries are there with the sport and commericial industry in mind...I will ask Al for his imput on this and let you know.
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Good points Gooey. I read that over three times and tried to pick out a few things, so here they are: ;)
Recessive alleles are not necessarily the negative traits.
What is the difference between mating of two hatchery spawners that both are heterozygous and mating of two wild spawners that also are heterozygous?
Normally natural selection favours strong individuals (ie. bigger fish, more aggressive fish, larger spawners, resistant to disease). I do not totally buy the theory that hatchery stock will extinguish the population because selection favours them yet they are the ones supposedly have the weak alleles. If the third generation of the hatchery or wild strains are homozygous recessive, and let's say the recessive allele disadvantages them, wouldn't that eleminate them in the population? This would then favour those who are homozygous dominant or heterozygous, and the process continues and the % recessive allele will be lowered. What you are saying is, the first generation will be all good as they are either homozygous dominant or heterozygous, but eventually in the third or forth generations, all of a sudden they all become homozygous recessive and that will wipe out the population. What is the chance that the physical trait of the recessive allele becomes dominant in the population when selection favours the dominant allele 3:1?
This doesn't mean I don't believe hatchery has a negative implication on the population. The major negative impact usually lies within the juvenile stage, which a lot of people often neglect. Competition between hatchery and wild juveniles usually favours hatchery fish as they are bigger and stronger. Competiton maybe direct or indirect. Direction competition is caused by competing over space. Indirect competition is caused by the race for the limited amount of food in the wild. First year marine survival rate is dictated by how well the juveniles do in the stream before smoltification. If the ocean condition is not ideal, then usually the hatchery smolts will win.
Saturday afternoon, I am talking about genetics.... ::)
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To answer your questions:
No, not all recessive genes are negative but remember that with a hatchery brood stock many more fish make it thru the early phase of life when natural selection would have culd the weak out. Once they get their foot hold (make it thru the first year or what ever) then they have a better chance of over coming many of those selective forces and returning to spawn. Keep in mind too that recessive genes probably have been selected AGAINST in the past and have become recessive to a dominant (more competative) gene that was selected for.
2nd question is a tough one...the main problem in mating 2 hatchery fish is that there is a high likelyhood that there will be a common blood line and hence complications with inbreeding. as well the hatchery fish were helped thru the first part of life and indeed the may pass on less than desirable genes where as the wild pair should technically be more competitive.
I agree that hatchery stock can't wipe out a run by eventually converting the population to homzygous recessive. It may make them more suseptible to a catastrophy tho like a disease tho. I think the main concern is that after a while most of the natural gene pool will be lost and you get a run of runt fish (Capilano is a great example). There are some nice 8-10 lb fish in the cap...maybe they are the Homozygous Dominant. Lets assume the cap was fully restored to its former state (particularly spawning ground) I bet if the current gene pool on the cap was used to repopulate it, the run would die out relatively quickly. Its only because the hatchery pumps out hundreds of thousands of smolts that the get 20-30,000 runts back.
Thanks for the mental work out there. Dont know if everything I said is bang on...its been ages since I referred back to my genetics that much!
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The first part has a very good point about hatchery raised juvenile would do better in the first portion of the life cycle where natural selection is at work big time, so negative recessive alleles get a free ride into the population.
What about ocean adult and spawner phases though?
Do hatchery raised fish compete just as well as wild strains when obtaining food in the ocean?
Do hatchery fish spawn just as well as wild fish (fecundity, survival rate of eggs, etc)?
Ok two more questions, almost.... ;D
1. Why would first generation hatchery fish (produced from two wild fish) be worse than first generation from two wild fish in the wild?
2. What is the chance of two hatchery fish end up mating together in the river?
I'll attempt to answer both (you all can stone me at the river cleanup if I am wrong ;D ):
1. Having two wild parents artificially spawned is not necessarily bad, but not perfect either. The wild parents receive a free ride to the hatchery comfortably. They sit in the hold tank until they reach sexual maturity, then they are artificially spawned. This process eleminates the selection that is so crucial in the population. It removes the choosing process, which maybe filtering out the weak ones. Strong males that can compete, swim well will get the female that has the most eggs, spreading its strong gene in the end. The largest male isn't necessarily the strongest male. If two fish are mated in the hatchery simply because they are big, the offspring just might not be the strongest that can be produced.
2. The probability of two hatchery fish mating in the wild will correspond to the ratio of hatchery vs wild fish in the entire population. Someone else brought up that hatchery monitors the population to decide how many fish are raised, to eleminate the chance of two hatchery fish spawning. Right?
The above scenario can then be related to the likelihood of inbreeding.
Does this next statement make sense?
The chance of inbreeding (fish from the same parents mating) is smaller if more hatchery fish are produced? If 200 parents are used as opposed to 100, the chance that fish from the same parents meet up would be smaller right?
To further prevent inbreeding, would hatcheries choose a variety of spawners (big, small, skinny, fat, fish that make to the top, fish that only make it to the lower river) to mate?
Would this explain why a large system such as the Vedder is still able to be so productive in terms of quality and quantity since it has a large number of fish to work with originally?
That's all for now, it's Saturday night after all. ;)
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Rod, question #1 you posed...you answered it yourself already: "hatchery raised juvenile would do better (re higher survival rate) in the first portion of the life cycle where natural selection is at work big time, so negative recessive alleles get a free ride into the population". And may I ad you summed it up very nicely too!
You asked: "The chance of inbreeding (fish from the same parents mating) is smaller if more hatchery fish are produced? INCORRECT, its higher. One naturally spawning pair may procude 6 returning adults. take that same pair into a hatchery, and take their 3000 offspring, keep them in pens, feed them, protect them, then release them once they are stronger and you get WAY WAY more returning fish from that brood! More brothers and sisters in the river = higher chance of inbreeding = greater chance of negatives genes surfacing!
Thats why the vedder and chehalis have a 4 hatchery kill limit, they want to limit/minimize the number of hatchery fish from spawning!
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intellectually, i felt that the last couple of posts, to be very exhausting. biology, fortunately is not my background.
in laimens term, i guess what it comes down to is.......
the process of natural selection has been going on for millions of years. any attempt to 'short cut' or even interfere with its course can create an imbalance in the final out come. any harm or mistakes, may prove irreparable.
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Out of curiousity Blade, whats the highest level of education you have achieved?
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More brothers and sisters in the river = higher chance of inbreeding = greater chance of negatives genes surfacing!
Thats why the vedder and chehalis have a 4 hatchery kill limit, they want to limit/minimize the number of hatchery fish from spawning!
Typically, different populations of the same species harbor different recessive deleterious alleles, so hybrid offspring between parents from the two populations (in this case hatchery and wild) will not be homozygous for the same deleterious alleles. The offspring are fitter than either parent because the effects of the deleterious alleles have been masked. If the hybrid offspring are allowed to mate randomly in subsequent generations, the deleterious alleles will segregate out because of the mechanics of Mendelian inheritance and produce individuals homozygous for the same deleterious allele, which will have reduced fitness. But the mean level of fitness in the population will still be higher than the level in either parental population, because the frequency of each deleterious allele has been reduced by mixing.
;)
uhmm... I went to grade ten, does my post stil count?
;D ;D ;D ;D ;D
j/k
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Gooey: Good point regarding higher return of spawners from hatchery parents than wild parents, I did not factor that in. But, how many more returning spawners would we get from a hatchery pair than a wild pair? Double?
The definition of inbreeding also needs to be clarified. Is inbreeding simply mating of offsprings from the same parents? Or are we assuming inbreeding as mating between hatchery offsprings?
If it is mating between offsprings from the same parents, the probability of a brother and a sister coming together also depends on the overall population size (bigger the population, smaller chance). If inbreeding is mating of all hatchery offsprings together, then your explanation regarding bigger hatchery population = higher chance of inbreeding would definitely be true.
Buckeye: The first portion of your post "Typically, different populations of the same species harbor different recessive deleterious alleles, so hybrid offspring between parents from the two populations (in this case hatchery and wild) will not be homozygous for the same deleterious alleles." doesn't seem too correct. Are hatchery and wild offsprings so genetically different that we can classify them as two different populations? Since both wild and hatchery offsprings come from the same population (hatchery offsprings from wild broodstock), how can they end up with different recessive deleterious alleles?
Population is defined as a group of organisms that inhabit a space and do not interbreed with other groups. For example, limnetic three-spine stickebacks come in two different varieties due to changes during post-glacial period. One group only occupies top water-column while the other occupies the bottom water-column. When putting both populations into the same fish tank, they do not interbreed as both exhibit different sexual dimorphism (they both exhibit different physical attributes (mainly size) that make them not interested at each other). The difference in those physical attributes is a product of evolution of genes during the last glacial period when they were separated.
Because the hatchery and wild groups are so similar genetically and physically, you can't classify them as two populations as they still breed with each other.
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Out of curiousity Blade, whats the highest level of education you have achieved?
One's level of intelligence and knowledge on a given subject is not limited by or directly linked to their level of education. Personally, I think the education system in this country is a farce and one's level attained in that system is meaningless.
I must agree with gman! One's level of education doesn't mean much. Common sense or knowledge of any subject can be achieved without earning a degree in University/College. Anybody can learn anything as long as their willing and have the passion to learn. There are so many sources to obtain info about anything (computers, libraries, friends, etc.)
Like i said b4......Gooey.....why do you need to try and put others down? If Blade is wrong.......why don't you correct him and explain otherwise. I don't see Rod asking you if you're a moron........even if he disagrees with some of the things you say.
Sorry Rod for the last statement......this guy's such a downer :(
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First off, asking one what level of education they have should not be seen as an insult (sorry if it was). The main reason I asked, was that much the information I was drawing back on was from biology in grades 11 and 12 so I was just trying to find out were blade sat in that mix. I absolutely agree that passion, ambition, and drive will take a person a long way too.
Rod and I were getting into a fairly indepth conversation and if it would have been beneficail ( to the forum) to dial back the technical lingo...I could have. I usually look at someones profile before I respond to them. I notice many people 30 and above and not many teens...I think many of the members in their teens and early 20's arent putting their ages on their profile so it is hard to know what age of person you are talking to and you cant taylor/temper what you are saying quite as well.
Any how...back to genetics!
Rod you are correct: "Since both wild and hatchery offsprings come from the same population (hatchery offsprings from wild broodstock), how can they end up with different recessive deleterious alleles"?
If hatcheris mixed the source of the gametes ie sperm from males of one river and eggs from a female from another system then infact the offspring would probably indeed be MORE competative. this is a theory known as hybrid vigor. Basically is dictates that when 2 different populations are cross bread, the strongest traits in each gene pool would be expressed in the offspring. Unfortunately I dont think hatcheries mix their gamete sources (they all come from on river/one population).
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Just spoke with the cap hatchery and return rates (% of hatched fish that make it back as adults) ranges between .5-7 percent. Wild fish are on the lower end of that spectrum as compared to hatchery.
Thats quite a difference (14Xs) if you take either extreme. On a batch of 2000 eggs, thats 10 wild adults (.5%) compared to 140 hatchery adults (7%).
WOW
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Out of curiousity Blade, whats the highest level of education you have achieved?
In Biology, grade 12 (barely passed).
In marketing and business administration, post secondary (college and university).
In the school of 'hard knocks', still learning.
.....what's your point. How far did you go?
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same sorta story...all over the board in high school, took math11 3 times to get a high enough grade for college, at the same time pulled A's in the sciences. After that 3 years general science, 2.5 Business... none of my education is particularly applied to my current employment but none the less valuable to who I am as a whole. In the last 2.5 years I have had 2 additions to my family, ask me what the has taught me about life!
A lot of what we were talking about was from bio 11 (punnetts square etc) and indeed I read most of those post more than 2 times before replying! I would like to get feedback from someone with a more current involvement in the genetics fields as I am rusty and the field of genetics is still exponentially growing.
If indeed this conversation is too technical then it would be best to dial back the techi talk so more can benefit from the dialog! Really what we are talking about, IMFO, is quite fascinating and I wouldnt want to loose someone with all the jargon etc. Maybe I am drawing on more of my university genetics than Highschool Bio!
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same sorta story...all over the board in high school, took math11 3 times to get a high enough grade for college, at the same time pulled A's in the sciences. After that 3 years general science, 2.5 Business... none of my education is particularly applied to my current employment but none the less valuable to who I am as a whole. In the last 2.5 years I have had 2 additions to my family, ask me what the has taught me about life!
A lot of what we were talking about was from bio 11 (punnetts square etc) and indeed I read most of those post more than 2 times before replying! I would like to get feedback from someone with a more current involvement in the genetics fields as I am rusty and the field of genetics is still exponentially growing.
If indeed this conversation is too technical then it would be best to dial back the techi talk so more can benefit from the dialog! Really what we are talking about, IMFO, is quite fascinating and I wouldnt want to loose someone with all the jargon etc. Maybe I am drawing on more of my university genetics than Highschool Bio!
nothin' beats experience :)
as far as bio 11, that's been two decades for me. :(
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So I tried to post earlier, but something got screwed up. Dam hatchery computer.
Ok so my point was this (highly condensed this time because this topic seems to be exhausted).
Giving hatchery fish a better survival chance in combination with a smaller gene pool (parent fish) will result in dispropotionate level of the brood stock parent fish genes returning to the river. This means an inbred population if the hatchery:wild ratio is high enough.
Point 2. Don't the fishery people encourage the killing of hatchery fish when caught? I think so. On the vedder, they kill them in the hatchery according to my sources, and they also truck them back down river. So many of those fish are removed from the population eventually.
Anyways, just a thought.
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well even though some off that lingo was a wee bit over my head ;)
i think i got the jist of it lol
so what about letting natural selection do its thing within a hatchery setting, would take some reconstructive surgery but think about it down and dirty nasty pads for all those bad boys and girls. then when theyve dug in laid them down and laid out there life force, remove dead boddies, control temp of water, control flow of water through tank wait for eggs to hatchthen remove the fry or alvien and place in a more controlled enviroment for remainder of hatchery life.
say large long troughs with 20 pair of fish or so if a certain fish has not been able to find an appropriate mate within ten days move him or her to another tank
or go to the extremes that the atlantic salmon federation has and organise the gene pool and keep tabs on returning fish through proper I.D. pit tags so that you can keep the gene pool as seperated as possible. time consuming at first but once the initial field work is done its a very easy system to track.
cnm
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I guess it all really depends on what the goal of the hatchery is...is it to fortify a run or to provide a resource to comercial and sport fishers.
My feeling is that most hatcheries arent meant to protect wild stocks, they are there to provide a fish that is destine to be removed from the population.
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My feeling is that most hatcheries arent meant to protect wild stocks, they are there to provide a fish that is destine to be removed from the population.
By your definitions, it is impossible to fortify a run with a hatchery. Anything that improves the survival rate will weaken the stock by limiting the effects of natural selection.
The only way to truly fortify a wild stock is to create more spawning and rearing habitat and limit harvesting.
That said, if we want more fish sooner, the current system of using only wild fish for hatchery brood stock and limiting the hatchery output relative to the wild stock is probably a good compromise.
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yes, I would agree...the key isnt pumping out more hatchery fish. I think probably mans biggest impact would be in the area of habitat restortion.
The whole hybrid vigor thing is a interesting idea (introducing genes from another population ie egg or sperm from a different river). Basically a coho is a coho regardless of river so I don't see why they dont take eggs from one river, sperm from another and introduce that brood to a new river...seems like introducing new alleles/genes into a river is better than letting weak ones sneak in thru excessive hatchery returns and inbreeding issues.