Thursday, October 29, 2009

Interesting and Large Bass Experiment

If I had a top ten list of favorite things, I would have a tuff choice in the middle of the pack choosing between Reese's Peanut Butter Cups and a new Fish stocking experiment! I just can't ever seem to get my fill of either.

Anyhow, enough of the nonsense as I try to make it through the rest of this yet another rainy day. This interesting pond that we electrofished for Pat Mcsherry last week was not necassarily meant to be a fish stocking experiment by design, but falls into that category by default. I have been researching and fooling around with different stocking combinations of low density predators with high density forage and Pat's pond just fit the bill perfectly.

Based on a foggy memory and some observations we estimated that the pond had a huge fish kill about 4 winters ago. The pond is very fertile and simply produced more fish biomass that summer than it could support through a harsh winter and the biggest fish simply suffocated to death. As the fish started dying, their decaying bodies only used up more and more of the available oxygen under the ice and pretty much all the fish died. Well to make a long story even a bit longer, all of the smallest fish in the pond found enough oxygen to survive the rest of the winter.

There were 1000's of small fish that survived the winter kill and absolutely no large predators to eat them. So many that the fish became instantly stunted, as they all competed for the same tiny peices of available food. That basically set the stage for a very low density predator/high density forage situation. When we electrofished this pond, it was completely full of tens of thousands of small crappie, tiny bluegill and little bullheads. The problem was they were all adult fish with huge eyes like this one.

While there definitely was not a natural balanced fishery at hand, what we did find was just about what I told Pat to expect, I kept telling him that we were going to come across a handful of nice big bass as we were dialing up scores of adult midget fish. Small bass would survive the fish kill as well, and a few of them would make it big enough fast enough to avoid the huge stuntedization of the rest of the population. Then they simply would have as much to eat as they could ever desire! When we did start to find some bass, I didnt expect them to be quite like this: morbidly obese! Look at the size of their mouths in relationship to their bodies.

The average bass in this pond is 18.8 inches long with a relative weight average for the lake of 125%! The biggest bass we sampled was 20.5" and weighed 108 oz. with a 138% relative weight. A typical 20.5" LMB should weigh 78 oz.

You can actually learn quite a bit about LMB by observing this sort of scenario. I have electrofished and analyzed well more than 100 lakes and ponds across the midwest this year and can tell you this- If you want to truly grow big bass, you can do that much easier and faster by stocking just a few per acre and harvest them like crazy if they even think about making babies!

This may sound strange to many, but the average ADULT bass in Illinois is 12 inches long. If you wait until next year it will still be 12 inches long and if you let it grow up the year after that, its still going to be 12 inches! Many lakes and ponds will grow their original stocked fish well past 12 inches due to limited competition, and the first year class after that may hit 14-15 inches, but the large majority of their offspring will not grow much past 12 inches due to the increased and compounding competition, unless they are harvested, preyed upon, or naturally thinned down.

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