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PBH your life is a contradiction. You are a school teacher who spends much of his day on the web, need I say more. Teach your students to think for themselves and not just follow the system.[/reply]
ummmmm....no. I'm not a school teacher. In fact, part of my job (I'm an Information Systems Specialist) is to be on the internet. Like with anything else that is posted in a thread, you should check your facts prior to posting. Get them straight. You lose credibility when you don't have your facts correct.
Any other contradictions you'd like to point out?
I don't know what you do for a living. I don't care. I'm not going to try to make an assumption of how well you do your job based on how often you post on fishing forums. I'd recommend you do likewise.
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When we take out the aggressive, fast growing, easy to catch fish we are in fact doing something along the lines of selective breeding. By eliminating those genes that have a higher potential to reach the full size of any one species and leaving the runts to reproduce.
But, that doesn't happen in a natural system. Even when we harvest those "aggressive, fast growing, easy to catch" fish. Think about it for a minute. When are those fish caught? Have they already had the chance to pass along their genes?
the answer is yes. Even when harvesting large fish, they have still had the opportunity to pass along their genes. We have not eliminated their genes from the pool.
Unless you are harvesting the "aggressive, fast growing, easy to catch" fish prior to them becoming sexually mature, then your argument doesn't hold. They are still mixing those genetics and passing them along to future generations of fish.
Harvest of the large fish doesn't breed out the large genes. Large fish have already passed those genes along.
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Professional fish biologist here. I'm finding this fish story hard to believe. The evidence seems to be wholly anecdotal, based on a fin clip and stocking records. One can speculate endlessly on how a younger fin clipped LT would end up in FGR. Someone claimed an otolith was pulled, cross section, and evaluated. Where is that info? Without that I'll remain unconvinced.
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[cool][#0000ff]BINGO. Without a numbered and recorded tag...and tag date...the whole story is open to speculation. We can accept the claims of the original biologist, or hold out for irrefutable data.[/#0000ff]
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[#0000ff]I can go along with the proposed theories of "diet interruptus", etc. But, I have spent time in the company of more thorough biologists...in California and elsewhere...who live and die by the real facts.[/#0000ff]
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[#0000ff]It DOES make a nice story...if true.[/#0000ff]
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[font "Tempus Sans ITC"][#808000][size 3]Come on TubeDude. You don't think the Wyoming Game and Fish Biologist believe in facts, give me a break man. I don't think our biologists promote false information or theories just because they can.[/size][/#808000][/font]
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[font "Tempus Sans ITC"][#808000][size 3]Here what is written in the weekly newsletter I recieved in an email. Also here is a picture of the fish.[/size][/#808000][/font]
[inline "Lake Trout.jpg"]
GREEN RIVER-- So you think you know how to age a fish, do you? Not so fast -- even the "experts" get fooled.
Wyoming Game and fish Department fisheries biologist Bill Wengert, a 35-year veteran, found out just how tricky it can be to age a fish recently when he caught a lake trout on Flaming Gorge Reservoir.
"I was ice fishing in the Big Bend area when I caught a lake trout weighing a very skinny two and a half pounds and measuring 22.75 inches in length," Wengert said. "The fish showed no signs of any obvious hook scars, not saying it had never been caught previously, but a lot of lake trout in the Gorge are hooked-scarred. I thought that was unusual.
"As I looked closer I noticed the adipose and right pelvic fin of the lake trout had been clipped, so I knew the fish was stocked. Looking back in time to Game and Fish historical stocking records for Flaming Gorge Reservoir I determined the fish was stocked on April 14, 1983, at an average length of 8.3 inches. The fish were loaded onto a barge and transported to the middle of the reservoir off of Buckboard Bay. Only 11,656 lake trout were stocked on that day. This means the fish spent nearly 25 years in Flaming Gorge Reservoir and was 26 years old, including one year in the hatchery."
Fisheries biologists use scales, fin rays, bones and otoliths ('oto' means ear and 'lith' means bones) to determine the age of fish because these fish parts often form yearly rings (annuli), just like a tree. Otoliths help the fish keep its balance in the water. When an otolith is removed from a fish, sectioned into thin slices and viewed through a microscope, it reveals a series of growth rings. Otoliths are more commonly used to age fish because they provide the most accurate ages, particularly in older fish. The Otoliths were removed and examined from this particular fish. The examination verified the age of this fish to be 26 years old.
"I have looked at thousands of fish in my career and I never would have guessed that fish was so old," Wengert said. "What is really amazing about this whole event is that, from my perspective, I may have actually clipped the fins on this very fish and I know I was driving the barge when the fish were stocked, nearly 25 years ago."
Wengert says long-lived fish, such as lake trout, are like humans in that they vary in size no matter how much food is available to them.
"A fish's genes also determine how large they will grow. Some fish are programmed, if you will, to be large and others, small," he said. "That applies to fish from wild populations to those reared in a fish hatchery. There was plenty of food for this one lake trout to eat when it was stocked 25 years ago and it only grew to be two and a half pounds."
Data on the length-frequency of lake trout from gill nets set in Flaming Gorge Reservoir from May 1990-2004, revealed that, in 2004, one fin-clipped lake trout measuring 35.6 inches and weighing 17.1 pounds was captured in the Big Bend area. This fish was stocked the same time as the much-thinner fish Wengert caught through the ice.
"When you think of the record lake trout taken out of the Wyoming portion of Flaming Gorge Reservoir, 51 pounds, this fish paled in comparison in size, but its capture allowed fish managers an opportunity to learn more about fish genetics, age and growth of lake trout in the reservoir," he said. "The adage is true: You can learn something new every day."
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[cool][#0000ff]Sorry. No offense intended to either you or the biologist. The otolith test proved that the fish was indeed the age projected. But, fin clips are subject to more potential for error than are numbered tags. That is the only point I was trying to make.[/#0000ff]
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[#0000ff]Ol' Bill has an impeccable reputation and plenty of experience. I don't think anybody could really challenge his statements.[/#0000ff]
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It appears they aged the fish. I'll buy what they are selling but it barely adds up.
Consider this: there is an extremely low probability that any of the 12000 fish stocked 25 years ago are even alive today. A low annual mortality rate of 35% leaves less than one fish (0.25 fish) alive 25 years later [in excel =12000*(EXP(-(-LN(1-0.35))*25))]. The chance that a remaining fish from this stocking event is a wildly stunted individual puts the probability off the charts...
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Wow PBH I did get you and your bro mixed up. You, your bro, and worm and bobber all sound the same to me anyway. Maybe you were all brainwashed at the same time. And for the removal of the genes before reproduction happens all the time. I don't think it is an issue at all in the gorge. Think of the Berry. If we had a smaller slot on the Berry think how many wouldn't ever make it to spawn. Even at 20" I am not sure how many of the better genes would be removed before they ever spawn. I am very glad we have it at 22". In fish it is amazing how quickly you can manipulate the genes. I know first hand and have seen it many times over.
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tight -- I still don't agree with you.
A fishes genetics are there from birth. A young fish (small fish) still may have the genetics to grow big. So, if a sexually mature fish contributes in the spawning process, it still passes it's genes on to future generations.
Let's do a hypothetical scenario at Strawberry. Pretend you have a cutthroat that is born with "superior" genetics. This fish has the genes in it to grow to phenomenal sizes. By age 3 this fish might be 12". The next year its closer to 17". Is it a trophy? Not yet. But it is sexually mature, and it is currently spawning and passing it's "superior" genes on. The fish then reaches 18" and is caught by an angler who decides to illegally harvest the fish. It's dead. It never reached its size potential -- but it already passed on it's superior genes, most likely multiple times. Those genes are not lost. This is why you can't hardly breed out the genetics in a natural system. The fish are spawning and passing on genes long before they ever reach trophy size. The genes don't magically change during the lifetime of the fish.
On the other hand, take another newly born cutt that has "inferior" genes. Maybe this fish is only programed to grow to to 23" in size max. Again, this fish reaches sexually maturity and begins to spawn prior to the fish ever being removed from the system. At size 23", it is caught and removed -- but it has already passed on it's inferior genes -- numerous times over.
The difference with your cichlids at home is that you can weed out the small fish and not allow them to reach sexuall maturity. You can prevent them from ever passing those "inferior", or undesirable, traits to future generations. You leave your biggest fish in the tank and allow them to continue to breed, then again remove the smallest. It's easy in captivity where you control who is doing the breeding. You can't do it in nature where you have no control over who's doing the breeding.
So, at the Berry -- even if you lowered the slot limit to something like 17" -- those fish are still spawning and passing on their genetics to future fish. It doesn't matter the the spawning fish haven't reached their maximum potential size -- potential doesn't change the genetics. The genetics are there from day 1. Cutthroat in the Berry should be reaching sexual maturity at about 14". Unless we are harvesting every fish prior to sexual maturity, then all genes are being passed along, and the danger of breeding out "superior" genes is not a threat.
FWIW -- there are only two of us that ever participate in these forums -- if you are confusing me, my bro, and worm and bobber, then you are a very  person!
FWIW2 -- I'm damn good at my job. Don't ever try to judge MY job performance by how much time I spend on BFT. I can attest the same for worm and bobber. Shall I pass you along some references?
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PBH,
I don't care any more if you agree with me or not. I just don't want you to feel it is your job to brain wash others as you have been brain washed. As an IS guy I don't doubt you do a good job at it. You are tenatious enough and certainly hold your ground on what ever you believe is right.
On the genetics my experience is not simply from cichlids in an aquarium. I have also had experience with trout, sunfish, bass, and even some invertabrate aquaculture. I have dealt with millions of spawns with over 1000 of species of fish. Yes many were cichlids but definitely not all.
I don't believe that the rainbows in the berry if fertile would be ready to spawn at 16" I don't know on the cuts, but I would tend to believe there are many at 15" one spring and 17" to 18" in the winter. That means they get caught in that winter and they never had a chance to spawn. They were removed from the gene pool. Either way I don't think it is a huge issue in Utah. I do however believe that genetics play a larger role in fish size than you or the Utah DWR believe. I think we just agree to disagree.
In the mean time you contiinue to fish for your planter rainbows and tigers and I will do the same when time doesn't permit me to go and chase after larger and genetically "superior fish"
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This thread is getting older than that mackinaw we were talking about !!
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