Northwest Fishing Reports

Can someone give me a clear description of the thermocline.

major change in water temperature and certain depths/levels in a lake.

I found this definition on one of my favorite sites.

Thermocline - The layer of water where the temperature changes at least one-half a degree per foot of depth. Basically, a layer of water where the rising warm and sinking cold water meet.

http://www.bassresource.com/fishing_lur ... tml#def106

I know back in the south when we are crappie fishing you start out the beginning of the year fishing in deep water for crappie, but as the water gets hotter the fish will move up because where the rising warm and sinking cold water meet there is not enough oxygen being produced in the water which causes crappie and other fish I am sure to move up to the warmer water where all the vegitaion is growing and producing oxygen. That is just what I have always been told.

Jason

I took a oceangraphy class years ago in college, but the same principles apply in larger lakes. Shallow lakes in warm eastern washington may not have a thermocline due to lack of depth. Anyway the thermocline is the depth in which the surface warmed water and the cooled up welled water from the bottom meet. This is important to fishing because the water being upwelled from the bottom is colder and colder water holds more oxygen at the same time the warm surface water contains most algee, single cell plant and animal life the fish like to eat. So if you can pin point the depth where the temp falls you will find fish there.

The strongest thermocline around here are in Spring after turnover has occured we have had a few 70 degree days.

There are 3 sections of the water. Upper, middle, and lower. The middle is the thermocline. During the summer this is key, at least for trout. The upper is too warm, the lower is colder obviously, but it is too cold for all the bait in the water, the single celled organisms or whatever, but the upper is to warm for the single celled organisms. So they all hang out in the thermocline, which in turn all the fish hang out in this water column. When you have a fish finder, its pretty easy to locate the thermocline, its just where all the fish are at. A few weeks ago I found it, at mineral. In 30' - 35' of water the thermocline was 19' - 23' down. But this can change almost daily, and in different water depths it will be different. The fishfinder I have tells the depth, then when a fish shows up it tells the depth of the fish, so it might be a little harder w/ a different fish finder.

Thank for all the info everyone.