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Read this article:
http://www.rockymountainanglers.com/imag...NW1996.pdf

Although relatively old, the article contains a lot of great information on why pike and walleye are NOT stocked more often in the Northwest.

From the article:
"Managers have repeatedly observed creation of a "predator trap," a large number of prey-limited piscivores (Peterman and Gatto 1978), after wall- eye introduction in other systems. Walleye predation led managers to stock larger trout or eliminate the trout fishery in Pathfinder (McMillan 1984), Keyhole (Wichers 1981), Alcova, and Glendo (WGFD 1990) reservoirs, Wyo- ming; and Salmon Falls Creek Reser- voir, Idaho (Partridge 1988). A survey of 15 major walleye-producing reser- voirs in Montana revealed that, al- though 3-4 reservoirs produce good walleye fisheries with catch rates near 0.3 fish/h, most are limited by inade- quate forage (Shepard 1991). Walleye appear prey-limited in most Wyoming reservoirs, with growth rate positively related to trout stocking density (Mar- witz and Hubert 1995)."

Sound familiar? This is the exact same thing that happens in Utah reservoirs…!
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Another good quote…

"We believe several factors contribute to prey depletion by walleye. First, reservoir water level fluctuations often result in wide annual fluctuations in abundance of yellow perch and other prey fishes; thus, walleye deplete the food supply in years of low forage abundance. Second, the lack of cover in many reservoirs during summer drawdown makes prey fishes highly vulnerable to walleye predation even during years of high reproduction of prey. This effect is exacerbated during successive years of poor reproductive success of prey and low water levels. Third, when recruitment of one prey species is low, alternate forage is often not available because of typically low prey diversity in western reservoirs."

What is the result of these prey depletions? A stunted walleye or pike fishery!

Again, sound familiar? This fits Utah walleye and pike fisheries just about perfectly...
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[#0000FF]Where are walleye stunting...or crashing?
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The crash is inevitable….right now we are in the boom cycle at some of our walleye and pike fisheries, but the bust will come!

Utah Lake and Willard are probably the only two fisheries at all stable as far as walleye go...
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are carp a suitable prey subsitute for pike?? I know carp get big fast but even smallish/ medium sized pike have no problem on 6 - 10 inch carp.
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The size of northern pike that actually consume carp will vary with the seasons. Carp are usually only a primary component in the diets of small northern pike during the summer months when juvenile carp are present. On the flip side, large pike will utilize carp throughout the year including the winter months. Generally speaking, the only carp consumed by small pike are little young of the year carp that measure less than 4 inches in length. But, in winter the carp that are consumed are greater than 4 inches and usually greater than 8 inches.

The problem you get with carp being a major food source for pike is that since they are only available for a short window of time, the small pike struggle to find food sources except for that time period when small carp are available. This will dramatically slow their growth throughout most of the year. In Yuba, as the population of pike grows and the number of small pike utilizing that small carp food source grows, growth will also slow. And, the number of pike converting to a larger carp diet during winter will also slow...and eventually you end up with a stunted population like Redmond.

So, the question is how do you avoid this from happening? Some are suggesting that we protect the large fish...and harvest only the small fish. It is true that by protecting those large fish you will have increased predation of carp; it is also true that by protecting them you assure that they remain in the reservoir. The question is whether or not this will help the fishery maintain and grow a large number of big predators and sport fish. With slowed growth rates in smaller pike because their primary food source is only available during the summer, fewer pike are going to reach sizes where they can utilize carp year round, and eventually the pike that are already big will be gone and you will have nothing to replace them!

Personally, I think the key is eliminating as many pike as possible to help increase the growth rates of the smaller pike. The reason we have big pike in Yuba now is because the pike had a head start on the other fish in the reservoir. This head start resulted in fast growth rates....as the reservoirs proverbial bucket, though, has filled the growth rates are undoubtedly slowing down. We need to harvest pike in order to get those growth rates high enough that small pike are converting to larger sizes of carp as a food source and are utilizing those fish year round.
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and why are carp always ignored on these things? think of how many eggs and fry, thousands of carp mow down each spring. that has to do a lot of damage on the recovery for prey. For every pike removed at yuba, there's ten times as many carp to take it's place to suck down the perch fry. I'd rather release all the BIG pike to eat as many carp as they can. remove the little ones if ya like tho.
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You are implying that carp are the limiting factor for perch….in truth, though, the limiting factor for perch is habitat. As the reservoir levels fluctuate and change, so does the habitat for perch and perch fry. IF that habitat is above the water and high-n-dry, you will not get good perch recruitment….that's the problem at Yuba.

Also, though perch eggs may be eaten by carp, perch fry probably are very rarely used as a food source for carp. Remember also, that those same carp could be mowing down the pike eggs and fry….but the pike seem to be doing just fine. So, what's the difference? It is lack of cover to escape predation by pike and walleye…

Also, pike will never control the carp population…carp are "ignored" because they are going to lay a gazillion eggs and avoid predation. Their numbers will explode with or without a high trophy pike population.
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[quote wormandbobber]You are implying that carp are the limiting factor for perch….in truth, though, the limiting factor for perch is habitat. As the reservoir levels fluctuate and change, so does the habitat for perch and perch fry. IF that habitat is above the water and high-n-dry, you will not get good perch recruitment….that's the problem at Yuba.

Also, though perch eggs may be eaten by carp, perch fry probably are very rarely used as a food source for carp. Remember also, that those same carp could be mowing down the pike eggs and fry….but the pike seem to be doing just fine. So, what's the difference? It is lack of cover to escape predation by pike and walleye…

Also, pike will never control the carp population…carp are "ignored" because they are going to lay a gazillion eggs and avoid predation. Their numbers will explode with or without a high trophy pike population.[/quote]

[#0000FF]The carp in Yuba are definitely piscivorous...and they feed heavily on baby perch...from newly hatched to several inches. They are one of the key factors in the problems of perch making any kind of comeback. Due to lack of suitable spawning habitat and/or nursery structure for perch, the perch only get a decent spawn in years when water levels are high. But whenever there are large numbers of perch fry you can see groups of carp chasing them into the shallows and mopping them up. And any lure that remotely resembles a baby perch catches carp.

The above is taken from personal observation and input from other anglers...not from a nebulous report from another state.
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[quote TubeDude][#0000ff]Where are walleye stunting...or crashing?
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is there not any current requests for additional walleye waters in Utah? The answer is: YES!

So, why not help educate the public asking for more walleye on potential problems that are common in western waters?

Those who cannot remember the past are doomed to repeat it.
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+1 for selective harvest on pike. let "most" of the big girls swim free..

I'm hearing the management strategy for Yuba is to eventually stock a sterile walleye, or saugeye? which, as I understand it is part of the reasoning to drastically reduce the number of Pike. not sure I agree with this strategy, as without reliable water levels sterile walleye will never have a reliable food source(perch), and most walleye aren't equipped to eat the 1+ yr old carp like a large pike can.
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[quote Tangled_not]
I'm hearing the management strategy for Yuba is to eventually stock a sterile walleye, or saugeye? which, as I understand it is part of the reasoning to drastically reduce the number of Pike. [/quote]


I guess one could interpret the management plan into something like the above comment.

The reason that the pike need to be drastically reduced is because the pike are drastically overpopulated!
The management plan calls for a "trophy northern pike" fishery. The only way to grow a trophy pike fishery is to reduce pike numbers through liberal harvest of fish. The current regulation calls for harvest of 20 under 36". The plan also calls for encouragement of harvest of pike. It's all for trophy pike.

Stocking sterile walleye are desirable because their population numbers could then also be controllable.

the management plan for Yuba is attached.
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Was that your answer to where are the Walleye stunting or crashing in Utah?

You would have been better off just saying you didn't know the answer.
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[#0000FF]Your arguments are beginning to sound like "Cliffese". Sorry, I couldn't perceive where you had answered my question. I fish most of the Utah walleye waters and the fish populations are down in some but the fish are all healthy. Reduced numbers are more a matter of poor spawning conditions or changes in regulations. No stunting.
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[quote TubeDude]
The above is taken from personal observation and input from other anglers...not from a nebulous report from another state.
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Hmmmm…just what out of any of the links I posted in this thread is "nebulous"? Those links state things pretty clearly….walleye and pike tend to deplete their food supply and stunt in many western reservoirs. What is so "nebulous" about that? (Something that has also been observed and documented in Yuba).

Also, the forage fish studies done on Yuba are NOT from this state…that is where I am getting much of my information about carp on Yuba. Again, hardly "nebulous"! Also, I have spent a lot of time at Yuba the past several years…some of that time has been boating and some of it has been fishing. I have NEVER seen carp schools chasing perch fry.

Also, you seem to think that your "observations" reflect reality….but they may, in fact, not! Sorry, but I totally disagree on the idea that the carp are a limiting factor to the perch….or the walleye making a comeback. In fact, I would say that pike are having a much more detrimental effect on the perch and the walleye than carp.
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Have you fished Yuba? Trust me, those carp do some serious damage on perch. Like tube dude said and I've personally experienced, I've caught some fat carp on 3-5 inch perch lures that I throw early spring. but I've also had biologists tell me pike won't eat carp, so it doesn't surprise me what I hear.
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You may have missed what Drew said in another thread…but, just so you know, a fish can "appear" healthy but, in fact, be stunted. Right now, walleye populations at many of our Utah fisheries are in the boom part of their cycle…so, they probably are healthy, but, again, the crash will come.
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sure, its a "short term" fix to thin em out. which from what I hear, is needed. but I personally don't believe overharvest of larger fish in the long term will lend itself to a true "trophy" pike fishery.

I believe the current pike strategy is paving the way for an artificial walleye fishery. which is fine, if that's what the sportsmen want...
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[quote utahgolf] I've caught some fat carp on 3-5 inch perch lures that I throw early spring. but I've also had biologists tell me pike won't eat carp, so it doesn't surprise me what I hear.[/quote]

I have spent a lot of time at Yuba the past 6-7 years….I have caught carp using many different plugs both in size an color. Just because I caught a carp on a rainbow trout colored jerk bait, though, doesn't make me believe they are preying on rainbow trout.

Start opening up some of those carp and look in their stomachs….you show me a carp and its stomach contents full of perch, and I will believe you. IN fact, I will come on here and gladly admit I was wrong. I have seen lots and lots of schools of carp in Yuba--big schools of carp--but, I have never seen them preying on other fish….not in May, June, July, August, September, or October.
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[#0000FF]My personal observations are just that. As a float tuber I get more "up close and personal" and can often watch fishy interactions from within a few feet. In the years after perch fishing was opened again on Yuba, and before the pike came thundering on, I fished Yuba more often. And yes, I did observe groups of carp acting like a wolf pack and herding schools of 1" new perch fry into small pockets and decimating them. There have not been enough perch hatching since then to create that scenario. Also, I HAVE "opened" a few carp for CSI purposes. I NEVER release a carp unharmed. And I have found perch up to 4 or 5 inches inside carp in Yuba.

As the man said when his wife walked in upon him and his secretary..."Who you gonna believe...me or your lyin' eyes?"

I respect your background and your overall knowledge of all things piscatorial. But I sometimes get weary of having every "layman" statement stomped into the ground with rhetoric and citations of non-related studies in other states that are largely not applicable to a specific lake or species. And I also resent the hell out of the fact that whenever anybody else expresses an opinion contrary to your own they are labeled as "ignorant".

"The crash will come". Yeah, and so will the apocalypse...and the millennium...and Christmas. Utah Lake has been producing lots of big walleyes since the 1950s, without help (or interference) from any government agency. Their population rises and falls with water fluctuations and subsequent forage species fluctuations. Right now they are in their multi thousands with many over 10 pounds. And all fish caught have copious visceral fat. They are not stunting.

Where do you predict the next stunting or crash of walleyes will occur?
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