lake balance

[johnr 47]

How does a small lake [ hoof/hicks/mcleish etc] keep such a large population of 11 to 13" walleyes year after year without yielding 13 to 115" fish [ next year class ] I have an example of a lake which is twice the size of boulevard lake that I fished in the mid seventies that produced large pike and various sized [ year classes ] walleyes. It was very hard to get to and began fishing other lakes for the next ten years until a logging road  made it a little more accessible [ 400 meters ] Fished the lake and caught nothing but hundreds or 9 to 11" walleyes.. no pike. Tried all summer but same result. Tried that same lake this year [20 years later] and caught 20 to 25" pike only...no walleye! Anyone care to offer some science....????

[mad scientist 140]

Could be a number of things going on, one would require a bit more information about the fish community and the history of the lake(s) in question, but I can offer some generalities.

 

It's not unheard of to see stunted populations of walleye in small lakes, particularly where it's an introduced population...introduced predators in small systems can rapidly deplete the natural prey base.  Walleye can be pretty variable with their growth and age at maturity...populations under stress tend to reach maturity at a younger age and smaller size than in healthy populations, so we might expect such a stunted population chug along for quite some time.  But walleye are also highly cannibalistic, especially when no other prey is available, so eventually the population could be reduced.  Add to that competition and predation from pike, which seem better adapted to small lakes in this part of the world, and eventually you could see the stunted walleye population disappear altogether.

[RickS 19]

So there is quite a bit going on with your post and these are just some guesses-- I would hesitate to call it "science" other than being based on basic fishery biology principles.  

 

Your question about small lakes with lots of 11-13" walleye suggests that a couple of things might be going on.  Walleyes do reasonably well feeding on minnows but to grow to large sizes they do best when they can get fatty fish like whitefish or they have very large populations of minnows.    Small lakes have less productivity capacity so it is quite possible these lakes just cannot produce enough minnow biomass to support a good population of large walleye.  You could also be seeing the effects of over-harvest resulting in few to no fish >13".  It is probably a combination of these factors.  You didn't mention anything about other predator species or what their population structure looks like.  It their population structure is solid, they could be out-competing the walleye for forage.  It their population structure also seems "stunted" then that is more evidence of insufficient forage.

 

For the lake with the logging road, I would guess that the easier access has resulted in over-harvest of the walleye population (perhaps to the point of a complete crash).  It is somewhat surprising that the walleyes seem to have been eliminated, but if that is the case, it would partially explain why you aren't seeing big pike too as we all know that walleyes are a favorite prey item of pike.  It takes a lot of minnows to support a 40" northern as compared to 10-15" walleyes.

[Captain Hook 17]

I find that the proliferation of bass in many lakes over the past few years, has a much more detrimental effect on pickeral populations than pike do.