Thread: Educate Me On Thermocline

Originally Posted by Cane Pole

Never seen a thermocline here on Ky Lake in my locale. Mainly because of depth which is average 12 foot. You can watch the rise and fall of plankton on the sonar starting about dusk and ending before dawn though. You can also see plankton migration. Some folks think that the plankton migration is the thermocline. I have seen miles and miles of migrating plankton.

Water changes levels here constantly, so not much time to set a thermocline.

You can smell the turnover of the lake sometimes. Smells like rotten eggs.

All the eggbeaters running up and down the lake keep the water churning which aerates the water and spreads the nutrients.

Dang, I had no idea KY Lake was that shallow...I always thought it was like Cumberland??
Interesting.

Originally Posted by INTIMIDATOR

Dang, I had no idea KY Lake was that shallow...I always thought it was like Cumberland??
Interesting.

Not even close, Intimidator .... KY Lake is a lowland reservoir & Lake Cumberland is a highland reservoir. Average depth of KY Lake is 15ft, while the average depth of Lake Cumberland is 90ft. Surface acreage at Summer Pool : Cumberland @ ~50,000 acres & KY Lake @ ~160,000 acres.

"You can watch the rise and fall of plankton on the sonar starting about dusk and ending before dawn though". I have seen this on my sonar in the lake I fish also.

Originally Posted by scrat

"You can watch the rise and fall of plankton on the sonar starting about dusk and ending before dawn though". I have seen this on my sonar in the lake I fish also.

You won't see that at our lake because it is so full of plankton and algae...our lake is deep and fertile, plankton and algae thrive ....it's also the reason we are able to sustain such a huge shad and fish population in a 2500 acre lake.
Having a fertile reservoir in the middle of farm country has benefits but also drawbacks. Once Blue/Green algae is established, it is a terrible battle to fight in the summer!
Even though our water is heavily stained, you can see distinct Thermocline features...sometimes the thermoclines will be in certain areas on day and move around a week later.
when we do get a Bad Thermocline, because of all the oxygen use by all the fish and microscopic critters, it sets up at 13 feet in the entire lake and NOTHING will be below 13 feet....this BAD Thermocline will last until the Fall Rains.

Great and useful info. And thanks for the screenshots.

Plankton on the rise right after sundown on the left screen.. You can see the fish on the stakes. Billbob pulled in a 2 pounder here.

Sometimes the plankton form a thin like belt a foot or two off the bottom. I don't know why. This is what some folks believe to be a thermocline when it is actually zooplankton.

When fishing late evenings around my place, you can see fish of all makes and models sometimes breaking surface and scooping up the zooplankton. They just swim around with their mouths open and get a belly full. When the fishes start breaking water near our dock, I pitch the a minner 1-2 ft below a bobber. I also burn the water with small roadrunners. Sometimes I git lucky.

Crappie Stalker and I have been out on Big Sandy mid day when plankton was so thick it looked like the boat was running on ground (0 ft on sonar depth) when we were actually in 20-25 ft water.

Originally Posted by scrat

"You can watch the rise and fall of plankton on the sonar starting about dusk and ending before dawn though". I have seen this on my sonar in the lake I fish also.

Can you explain what I am looking at in this pic? It all looks like a big mess to me. That is my main problem , I can't cipher what I am looking at on the finder.