Thermocline fishing

[cray]

I have been fishing a lake with what appears to be the thermocline at about 17 feet. I was told not to bother fishing any deeper than the thermocline so I have been fishing 17 feet and shallower. Is it really that simple?

[Rick G]

Not much usable oxygen below where the thermocline sets up.

[TruthWalleyes]

I like to fish anywhere from the center of the thermocline to 3 or 4 feet above. Yeah its that simple. Lot of large roaming fish found in thermoclines.

These were from last year, but the thermo set up between 17 and 28. Walleyes between 19" and 23"...Lot of em!

[MN_Jay]

I'm new to the concept of thermoclines. So how once you find out what depth the thermocline is in, how do you use that information to find out where the walleyes are?

For instance, do you find depths where the thermocline is at the bottom around some sort of structure? Thanks!

[TruthWalleyes]

Well, when your cruising around a big deep basin and locate the big arcs, start there.

Typically fish in the thermocline aren't moving around too much, so once pin pointed, you can concentrate your fishing, i also don't find them bunched up, more so spread out in an area. Much of their location depends on bait fish.

Depths where the thermocline is approaching the bottom...Yes i've caught walleyes there too, but other times those areas are deserted. Thermo walleyes require good electronics, gps, and often some patience to find out what bait they'll take. This year i'll be trying some vertical jigging as well as pulling spinners behind a DR rather than just trolling cranks. Eratic stops and starts can also help trigger the bites, also at times the bite can happen in a window and marginal fishing the rest of the time.

Good luck.

[no bait nate]

Truth, you've got some great advice and knowledge on fishing the thermocline for nice walleyes. Thanks for all the imput, and tips for us guys who this is a totally new concept. Once I upgrade electronics (hopefully next season) I hope to get out and take a stab at this myself. Let me know if ya ever need a fishing partner!

[ragged_edge]

Here in New Mexico we are fortunate to have some walleyes and northerns that were transplanted years ago. The lakes around here are formed from old lava flows and fairly deep. This past weekend the walleyes were found about 10' down and were located just above the thermocline. Anything lower suggested the dead sea. If, you do have a graph pay close attention to the concentration of fish at a certain depth as this indicates the thermocline

is just below them as shown in the above graph. Hope this helps........

All fish were caught by vertical jigging using homemade jigs black in color or black/chartreuse. These fish were feeding on crayfish....

[SpecialK]

Do all lakes have a thermocline? I fish a lake that is for the most part 6-8 feet deep but has a couple 14' holes. My thought is this lake is to small and too shallow to really have a thermocline.

[MN_Jay]

Thanks Truth, I appreciate the info. I just bought a new humminbird last year so I'm anxious to play with the sensitivity and go searching this weekend.

Edit: Forgot to ask my other question. Is it a foregone conclusion that below the thermocline will not have enough oxygen for the fish or does the oxygen deplete over the summer? If the latter is true, then is there a roundabout time this happens? Obvious temperature and each lake is going to be different but I was wondering if there were signs to look for that this is happening?

[MN_Jay]

Do all lakes have a thermocline? I fish a lake that is for the most part 6-8 feet deep but has a couple 14' holes. My thought is this lake is to small and too shallow to really have a thermocline.

From what I have read, all lakes do but eventually on the shallower lakes (like the one you refer to) the thermocline reaches bottom and eventually it's gone because the water on the bottom has warmed. These are the same lakes that will usually winterkill so if there are still fish there, it is probably spring fed. If you can find out where that is then I would concentrate there since the water temps will be lower and the oxygen levels will be higher.

[TruthWalleyes]

I would say NO not all lakes have thermoclines...Yes they probably do in very minute scales, but i find you need 30' of water or more.

As the thermocline developes, oxygen below depletes and continues to deplete until fall turnover.

Thermo is real shallow in SC MN right now.

[PerchJrkr]

You should be able to find the thermocline on any depth finder. Crank the sensitivity to 100% and you'll see the line. Figured this out years ago before i knew of leadcore and we'd find schools of fish and stop on them and jig around 15' down in 35' of water or so. We were always able to pick up a few, I think now if i went back with leadcore it could be a massacre! Lots of fish to be had in main lake basins, far far away from any structure..

[TruthWalleyes]

Lots of fish to be had in main lake basins, far far away from any structure..

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