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Discussion Starter · #1 ·
I understand the concept that a lake will hold warm water on the bottom during winter, and then in the spring it will switch from being warm on bottom to cold on bottom. I was watching some fishing show and the guy said that because the lake just turned over the water was cloudy and the conditions for fishing were bad. It got me thinking.. I fished a lake today that is normally pretty clear, but for some reason it was so cloudy that i could only see about 3 ft down. I figured maybe bluegills on thier beds could have stirred everything up but after i thought about it, it really wouldn't make senese for it to be THAT bad..
So could a lake that is really deep, but soft bottom change over and it cause everything to stir up like that? Also is now around the right time for things like this to be happening? And if anyone has anything else to add about the whole turnover thing, would you mind posting it in here?

Thanks...

By the way we only caught 4 or 5 DINKY bluegills and about a 10"er largemouth lol
 

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You are not the first person to say that the gils werent really biting good. All the reports I have heard from the past week or so pretty much seem to reflect that. Although I am no expert on gils I would have to assume that this has more to do with their stage of spawning than anything else.

As for cloudiness and turnover: I can only state what I know of some local lakes say Fremont for example its cold deep and clear but not for very long once the temps hit the 60's algae starts to bloom and it clouds up so I suspect the cloudiness from the bloom not from the "turnover" but their will be a thermocline between the warm water on the top and cold water on the bottom. Water has the greates density at (38 degrees ) so once the surface water starts dropping to 38 degrees in the fall it will mix due to the wind with the water on the bottom. (ie warmed in the summer) water creating fall turnover. In the spring since the water is warming not cooling it will mix (ie spring turnover) when all the water is the same temp say 38 degrees. We would be well past spring turnover at this point.
 

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Here is what wiki has to say about turnover: http://en.wikipedia.org/wiki/Thermocline

And as westlakedrive said we would be well past spring turnover. But you never know. I can imagine one instance that could produce something like you said, although there are probably alot more. Imagine a lake that had a huge sandbar or flat in the middle of it and on both sides of the flat there were deep holes. Let's say the main hole is 70 ft deep and continually fed by springs. The other hole is maybe 20 ft and not fed by springs. And let's say a creek drains the shallower hole. There would probably be a pronounced thermocline in the deep hole but not in the shallower one. As the holes warm up the big hole would turnover and drain into the shallower hole. As the season wore on the creek would keep draining the warmer, less dense surface water and maybe cause some kind of continual turnover? Who knows, Mother Nature is pretty complex and I'm no hydrologist. But anyways, I was fishing last week for bluegills and the majority had already spawned out. The water was real stirred up in one portion of the lake and then we saw about 20 carp in a group. We figured it was them. Also, I've seen a family of swans stir up the water pretty good looking for food.
 

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inland lakes dont usually "turn over". they are too small to get goin. the cloudy water was maybe an algae bloom or run off or a damn that opened up from another lake that drains into another by river. if it looked like mud, definitely not an algae bloom. if it was a green tint, than yes, it was algae.
 

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Johnny G said:
inland lakes dont usually "turn over". they are too small to get goin. the cloudy water was maybe an algae bloom or run off or a damn that opened up from another lake that drains into another by river. if it looked like mud, definitely not an algae bloom. if it was a green tint, than yes, it was algae.
No expert here, but wouldn't any lake that has a thermocline turnover?
 

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not necessarily. usually lakes turn over because of strong wind that can get a lake really rollin. smaller lakes are usually protected good enough that they dont get 3 or 4 ft rollers. higgins lake is one of a very few inland lakes that can get a turnover because it is large enough to get that kind of activity. really deep smaller lakes usually have thermoclines, but they usually stay towards the bottem because the waves cant get enough steam to get big enough to "roll over". there would have to be a huge spring to push the cold water up to the surface, i.e. lots of current pushing up against a shelf. watch lake michigan. when a strong west wind comes, the surface near shore gets considerably warmer, but when the westerly blows strong for 2 days, the surface temp plummets because the wind is forcing the bottom water up against a steep shelf, bring the cold water up to the surface.
 

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Discussion Starter · #7 ·
hey that wikipedia article explains it all... 39*F is where the water is densest, and when the surface water reaches around that point, you get spring turnover.. and when it starts to get cold and the surface water gets back around 39*F, you get fall turnover.. and right now everything should be settled and nothing changing.. so maybe after all the lake is just kind of silty?
 

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Johnny G said:
inland lakes dont usually "turn over". they are too small to get goin. the cloudy water was maybe an algae bloom or run off or a damn that opened up from another lake that drains into another by river. if it looked like mud, definitely not an algae bloom. if it was a green tint, than yes, it was algae.
Actually....most inalnd lakes in Michigan do stratify, and turnover twice a year (dimictic - two mixing events, one in the spring, one in the fall). Depth has much more to do with it then surface area. A lake or basin needs to be deep enough that mixing from wind cannot affect the bottom waters. If mixing is significant, the water is constantly being mixed and startification cannot occur. Stratification needs a strong temperature gradiant and calm conditions. Turnover needs relatively uniform water temperature and strong mixing. I could on and on....this is a large topic.

To answer the initial question....wrong time of year for turnover. My guess is algae, assuming there was no recent storm event. Can we have a little more info about the lake?
 

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Thanks for the clarification Brad. How does this stratification affect oxygen levels? Would fish usually be located above or below the thermocline?
 

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USMarine1171 said:
Thanks for the clarification Brad. How does this stratification affect oxygen levels? Would fish usually be located above or below the thermocline?
Shortest answer.....it depends, on a lot of things.

Typically, the cold water below the thermocline will hold more oxygen (more gas will dissovle at cooler temperatures). This is why fish that require high oxygen levels (lake trout, stocked rainbows, etc) can live in some deep inland lakes where there is a large amount of cold water below the thermocline.

Things get to be a problem late in the summer in lakes that have high nutrient levels. Large amounts of bacteria decompose organic matter on the bottom and use up oxygen. The thermocline prevents any mixing of oxygen from the upper layers and hypoxia (low oxygen) or anoxia (no oxygen) can occur. This situation is happening in the central basin of Lake Erie every August/Sept.

Where will the fish be...? Depends on the species. Bass, bluegill and other warm water species do very well above the thermocline. Salmon and trout will typically be found below or at the thermocline depending on other conditions. Coolwater speices like pike and walleye will move back and forth....resting in the cooler water, coming up to forage in the warmer water where prey is available.

Hope that helped.
 
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