Thermocline Question

[slaters#1]

can anyone tell me what water temp crappie seem to prefer during these hot summer months? the idea of dropping a thermometer down to determine temp appeals to me but i'd like to know the temps where the crappie are most likely to suspend. i fish ox bow lakes or farm reservoirs, usually never deeper than 15'. i have an inexpensive hummingbird fish-finder, i can see the fish but can't readily distinguish crappie from bass or any other fish. i'm thinking if i know the desired temp for crappie, this might help me better identify them on my screen. thanks for any responses.

[mbhutton]

I've seen that before but never new what is was. Good to know.

[BigRiverMarine]

Here is a thermocline on my unit at 30 feet.

Attachment 66872

Perfect example of a thermocline. .

[rocket rich]

I'''m still confused, show more of the thermo cline line's Not sure what i'm looking at??

[Team9nine]

Interesting, but believe it or not, we simply call it a thermocline. However, in freshwater the correct term is actually chemocline and the water is stratifying due to it's chemical composition and abilty to concentrate DO..

Not the same thing. Chemoclines are based around chemistry gradients and thermoclines are based around temperature gradients. There are others such as oxyclines (oxygen differences) and haloclines (salinity differences). In actuality, chemoclines are most predominant in waters that never mix (meromicitc). Most US lakes are considered dimictic (completely mix twice a year, spring and fall).

On most US waters thermoclines, which are usually correlated closely with oxygen levels (oxyclines), are the predominant factors to consider for summer fish locations. Most other 'clines' are going to be localized based on geography and related environmental conditions.

Here's a picture of a thermocline (the band of "clutter" around 18') taken from an old Lowrance X-70A unit. The weak image on the right half of the screen is what would happen on the older units if you cranked up the surface clutter settings.



-T9