Lake Temperature. Do you measure and how?

I just started fishing at Lake Sonoma in NoCal. I got skunked. People there said wait until Spring, but why? Fish have to eat, North California does not get that cold and people ice fish in the mid west.

Light or temperature, that is the different between summer and winter. We have already talked about "lake turn over", but we have not talked on what happens to the fish. I am aware of thermoclines and use to measure them.

Who has used temperature to determine fish ability and what piece of equipment have you used?

Re: Lake Temperature. Do you measure and how?

I'm not familiar with lakes - I'm on the Chesapeake.
But generally, some fish migrate (as you should know from NC), others hibernate - not all though.

Re: Lake Temperature. Do you measure and how?

As a Great Lakes troller on Lake Ontario, I run a Lowrance surface probe and a Moors' Sub-Troll 900 for down temp.
http://www.moorelectronics.com/fishing/fishing.html

These are great for when the temperature is stratified in the lake. In the winter, the strata disappears and fish either sit on the bottom or go to a depth where they feel comfortable with light level. (always by a food supply though)

Some guys love the Depth Raider for down temp. Copied technology from Moor but digital display rather than analog.

Tom B.
(LongLine)

Re: Lake Temperature. Do you measure and how?

Water temp is a VERY big piece of the puzzle. I'm assuming you were chasing bass and going to keep pursuing them. Read through this site as much as you can. http://www.bassresource.com/ Very valuable info there.

Re: Lake Temperature. Do you measure and how?

I have a built in water temperature sensor on my Eagle depth finder. Another thing that may have come into play on why you didn't catch anything is the type of lure or bait that you were using and the weather if it was windy or not.

They say if the wind is blowing out of the east they bite the least. I also try to pay attention to my fishing barometer. You can use a regular barometer to get an idea on how the fishing will be for the day before ya go out.

I personally like reading the bass fishing tips from some of these websites, like the website that gonefishie posted. They'll give ya an idea on what lures to use in what season, where to fish at on the lake durring a certain season etc etc.

Re: Lake Temperature. Do you measure and how?

I will start noting wind and light. I am also noticing time before dust and time after dawn. I will start noting water temperature. I am interested in thermocline. I have hear fish use thermoclines to ambush fish. Anyone hear of that?

LongLine said:

These are great for when the temperature is stratified in the lake. In the winter, the strata disappears and fish either sit on the bottom or go to a depth where they feel comfortable with light level. (always by a food supply though)

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I am using thermocline as the point or line that the lake temperature is stratified or that you notice a dynamic temperature change.

Does the Moors' Sub-Troll 900 tell depth? or just temp and speed?

wildmaninal said:

I have a built in water temperature sensor on my Eagle depth finder.

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Does the Eagle just show surface temperature?

Re: Lake Temperature. Do you measure and how?

ebry710 said:

Does the Eagle just show surface temperature?

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Yes I believe it does surface only. I have one of these older Digital Depth/Temperature Indicators made by Waller Corporation. It doesn't work due to a broke wire, can't figure out where it hooks to. Anyhow this thing will even count the depth in feet if I recall right up to 100ft. If this thing was working it would allow me to take temp readings at different depths. It even has a list of preffered temps for fishing all kinds of fish. Example: Bass 65 to 75 degrees.

Re: Lake Temperature. Do you measure and how?

ebry710 said:

I am using thermocline as the point or line that the lake temperature is stratified or that you notice a dynamic temperature change.

Does the Moors' Sub-Troll 900 tell depth? or just temp and speed?

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On Big-O during summer, you may find surface at 70F, then down 20 65F, then down 30 more & still find 65F, then down 20 more & find 54F then down 10 more & find 40F. The thermocline is that ten foot band, usually with 54F being the upper boundry. Just as important as a temperature change is that it's a density & oxygen content change. It only exists for a few months every year. Finding the thermocline is only the beginning. Every fish has its "desired" temperature range. Some above, some below, some in it. They will however leave their favorite range to feed.

Sub-T gives you down speed & temp specifically for downrigger trolling. The probe mounts on your downrigger cable so your bait is in that temp.(depending on length of line & type of lure) It transmitts a signal up the cable.

If you want to temperature profile the lake I suppose you could just lower the probe with the boat in neutral and look at your downrigger counter or even watch the cannonball on the sonar unit. We don't bother doing that on Big-O as the temperature profile over the same depth of water 1/4 mile to the east may be different than what you have where you are. The underwater currents in Lake Ontario are very dynamic.

What I have posted is really for open water. I'm not familar with your lake. If I were in your shoes, I'd get a really good fish finder & scout the lake looking for structure. I.E pinpoint drop-offs, holes, etc. I'd also fish around any stream or creek that empties into the lake.

Good Luck


Tom B.
(LongLine)

Re: Lake Temperature. Do you measure and how?

I use a handheld "Fish Hawk". It has a scale on the side as an example shows that Lake Trout hang out at water temps from 45-55 degrees. A temperature gauge on the side of it and a 3 digit line depth counter with 200 feet of line. A 9v battery powers it for years.

Once I've lowered the probe down to find that temperature it stays pretty much the same around the rest of the lake, so I roll it up and put it back in my tackle box unless I switch what species I'm going after like Salmon who stay around 50-57 degrees.

A Fish Hawk can be bought new for $249 or I bought two off Ebay one for $100 and $75 for the other. I resold the older one of the two. Fish Hawks have been around for many years. The one I sold had a light gauge too but their CS told me it was like 25 years old so I sold on Ebay and it bid up for $25 more than I bought it for.

Nice people in their customer service too.

Once I find the thermocline of the temp I'm looking for I then lower my down rigger weight and can troll away for many hours at that temp. The Fish Hawk at least solves 1 part of the equation. Your lure and color can be a big issue too as well as speed. I also use a Xmas tree set up or a big flasher in front of the lure as an attractor which can further excite the fish with the noise and flash as my lure color might be off for time of day and light penetration.

My Fish Hawk says Model #510/520 on it which is probably a 10 year old model. Some older models they no longer make replacement parts for so check with their CS before you bid.

The probe can also be attached to the down rigger weight but I don't find it necessary since the temp stays the same (water stratifies) around the lake at a particular depth. Don't know if it stays the same for salt water fishing.

http://www.fishhawkelectronics.com/520-Handheld-Depth{47}Temp-Gauge/26/

Re: Lake Temperature. Do you measure and how?

AHA, I found out where the wire hooks to on my temp reader, the one I mentioned earlier. This should be interesting to see how it works. I forgot all about this thing until I seen this thread, I bought it at a yard sale a good while back.

Re: Lake Temperature. Do you measure and how?

Expidia said:

I use a handheld "Fish Hawk".
Once I've lowered the probe down to find that temperature it stays pretty much the same around the rest of the lake, so I roll it up and put it back in my tackle box unless I switch what species I'm going after like Salmon who stay around 50-57 degrees.

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I did not see the Fish Hawk on eBay today.

So the thermocline stay practically constant. That is great to know. So you can find it, then run it.

Re: Lake Temperature. Do you measure and how?

LongLine said:

Sub-T gives you down speed & temp specifically for downrigger trolling. The probe mounts on your downrigger cable so your bait is in that temp.(depending on length of line & type of lure) It transmitts a signal up the cable.
Tom B.
(LongLine)

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That makes sense. You use the downrigger to tell depth the the sub-T to measure speed and temp.

Can you hook your line and troll at the same time?

Re: Lake Temperature. Do you measure and how?

wildmaninal said:

AHA, I found out where the wire hooks to on my temp reader, the one I mentioned earlier. This should be interesting to see how it works. I forgot all about this thing until I seen this thread, I bought it at a yard sale a good while back.

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I saw something like that on the web, but it was stand alone and did not hook up to anything.

Re: Lake Temperature. Do you measure and how?

ebry710 said:

Can you hook your line and troll at the same time?

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Yes. Check out the site I posted. They have a sketch of how to do it. Very often we run two lines off the probe downrigger. One at the probe and another about 10 ft above it. That way you can put one lure in the thermocline and a second lure at the top of it or slightly above it.

It's quite comon here when there are two guys fishing to use that setup and a second downrigger to stagger 4 lures and really cover the target area. I.E. probe rigger below thermocline at 70 ft with a stacker at 60 then 2nd rigger at 65ft with it's stacker at 55ft.

You can also run a single rod on each rigger and have 4 lures in the target area by running what we call "sliders" or "cheaters" on each line.

Tom B.
(LongLine)

Re: Lake Temperature. Do you measure and how?

ebry710 said:

I saw something like that on the web, but it was stand alone and did not hook up to anything.

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This is a stand alone unit, doesn't hook up to anything, and has a little handle in the back to slip your hand in.

I unfortunately jumped to conclusions about this unit. It was working when I touched the wire to where it is supposed hooks up but after a while of playing with it it quit working on me last night . So now I half to use my rusty electronic skills and remember how to test the little components inside. Maybe I can get it to work again, wish me luck. Sorry I didn't mean to hijack the thread, just thought I would pass on my little knowledge of these units.

Re: Lake Temperature. Do you measure and how?

wildmaninal said:

This is a stand alone unit, doesn't hook up to anything, and has a little handle in the back to slip your hand in.

I unfortunately jumped to conclusions about this unit. It was working when I touched the wire to where it is supposed hooks up but after a while of playing with it it quit working on me last night . So now I half to use my rusty electronic skills and remember how to test the little components inside. Maybe I can get it to work again, wish me luck. Sorry I didn't mean to hijack the thread, just thought I would pass on my little knowledge of these units.

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If I didn't want tons of info I wouldn't do iboats. Hijacking is only a problem if the thread goes to far astray. Thanks for the input.

Re: Lake Temperature. Do you measure and how?

ebry710...Skunked today as well! My son and I were out on our favorite High Sierra lake with no wind and no one else out on the lake. The water temp was reading around 43 and the fish finder showed a lake full of fish. We trolled for about 2 hours and figured they'd had too much turkey the day before! I'll be back for them in the Spring. It's time to put the boat up for the year. Snow storms are a coming! Even though we got skunked, there's nothing like being out in God's creation with your boy. It's a wonderful life!...Bob

Re: Lake Temperature. Do you measure and how?

Yep. I had mine with me when I went out last week. Best time out there is with my kid.

Skunk is just another challenge for next time.

Re: Lake Temperature. Do you measure and how?

I use an 840 Fish Hawk when I troll,but for leisure fishing a good fish finder that shows the thermocline will do just fine.
The most important part to successful fishing is knowledge.Learn the underwater structure and currents,then learn about your target species behavior and diet.This information is half the battle won before you start to fish!

Re: Lake Temperature. Do you measure and how?

rolmops said:

I use an 840 Fish Hawk when I troll,but for leisure fishing a good fish finder that shows the thermocline will do just fine.
The most important part to successful fishing is knowledge.Learn the underwater structure and currents,then learn about your target species behavior and diet.This information is half the battle won before you start to fish!

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How does a fish finder find a thermocline. Does it pick up the barrier or does it just register the fish not dropping below the line?