Within the State of Michigan, lakefront property owners associations have the nasty habit of taking over the control of their lake's ecosystems with the help of lake management "consulting" companies. There seems to be little input from our department of natural resources, so long as the property owners foot the bill for these changes. Now if you have to cross a swamp to get from the road to your home you need to file an environmental impact statement with the DNR to do so. In many cases, you are required to replace any lost habitat in crossing the swamp with other parts of your property. This isn't the case with our lakes. The consultants just happen to be directly linked to the very companies that will come in and poison off every weed in your lake. It's not like there is any conflict of interest involved here with the advice they offer to the property owners <insert sarcasm> on how to manage their lakes. So the answer is that these lakes are attacked several times a year with potent herbicides that kill of all of the natural cover the fish use in these lakes.
I have witnessed the results on many different lakes. The first year or so the fishing improves as the fish have less cover to hide in. The stringer fishermen attack the place taking out huge limits until the population has been thinned out. In the meantime, small fish such as young of the year fish can't find any cover to escape predation by the surviving keeper sized fish. Within another year or so, the adult fish in the lake have thinned out the prey sized fish to the point that there isn't enough forage to maintain good seasonal growth. This in turn makes the few fish that attain keeper size are rail thin. It may be hard to believe, but I have seen 10 fish limits (12" keepers) that weighed in at less than 10 pounds. While on many other lakes the average 12" fish weighs in at 1.25lbs, these fish will average in the .90 range. Those are not healthy fish.
Now there are times when the management company will miss a few weeds during one of these cleansings. As you fish along a drop off that used to have hundreds of acres of weed beds, you will happen upon a weed bed about the size of the typical dining room table. An amazing sight to see one of these beds as they look absolutely alive. They are! They are packed full of small forage sized fish of many species. And fishing around any of these places will result in automatic hookups of small undersized pike or bass that circle around these beds.
Think about it another way. Anyone who has hunted deer will be able to tell how many deer can hide or live inside of a large standing cornfield. They can also tell you how many deer stay in that field after harvest time. The same goes with a forest that falls before a clear cut operation. What once held numerous game animals now holds little. Granted, a clear cut forest is allowed to generate new trees which will someday hold more game, but bass aren't that lucky. These lakes suffer through semi annual clear cutting year after year.
My comment on some (not all) property owners comes from firsthand experience, and it can best be described by a conversation I had with one gentleman. As he was explaining to me how he just bought this lakefront home and was amazed at the amount of weeds the lake had. "They need to kill off all these weeds" was his comment. So I asked him in a nice way when he had purchased the property. Maybe it had been in the winter when ice covered the lake and he didn't really know what he was buying. Nope, purchased in July at the height of weed season! Just a simple matter of someone who bought a piece of property and decided to try to change the entire lake to fit his picture of perfect. It didn't matter that the lake had healthy natural weed growth in it. His ideal was a sandy bottom like Lake Michigan, and he wanted it on the entire lake.
The bottom line to me is that no fish is going to reach it's natural potential when it is forced to live in an unnatural environment. Bass or any other fish requires a number of things that nature has provided for it to live, and one of those things is natural cover in the form of weeds. It's only when humans want to try their hands at creating something that things go wrong.
