Lake turnover and fish behavior

YeeHaw · #1 10-19-2014, 08:02 PM

I have a basic understanding of how lake turnover affects fishing, and the drawbacks and rewards that come with it. What I do not understand is when and what temp they turnover. I was out on Wabamun last weekend, and the surface temps were only a few degrees above winter temps. So in my mind turnover should have been happening very as soon as the the surface becomes cooler than the water before the thermoline. Im I understanding this right, or am I missing something?

huntsfurfish · #2 10-20-2014, 09:43 AM

If it is close to winter temps, Wab should have turned over earlier and you might not see many signs of it by now. During turnover fishing can be tough, but should only last a few days.

Each lake is different. Shallow lakes will usually turn over earlier, deeper a bit later. Wind is also a factor. There can be quite a difference in time between lakes.

edit: Once surface water cools enough to eliminate the thermocline, you get your turnover.

I however, cant give you an exact temp.

dodgeboy1979 · #3 10-20-2014, 10:11 AM

when the surface reaches approx 4 degrees celcius it will turn over, that is when water is the most dense/heaviest

RavYak · #4 10-20-2014, 10:39 AM

What is the wab temps now? 3 weeks ago it was still 8-9 degrees. I haven't been out there lately since you aren't supposed to use large hooks now.

huntsfurfish · #5 10-20-2014, 10:58 AM

Quote:

Originally Posted by dodgeboy1979

when the surface reaches approx 4 degrees celcius it will turn over, that is when water is the most dense/heaviest

Pretty sure it doesnt need to get anywhere near that cold to turn over. I seam to recall seeing it occur in the mid to low 50 degree F. But I believe it can occur in warmer temps as well(it depends on the water temps at the bottom of the lake as well). Example: upper(epilimnion) 66 degrees, middle(thermocline)
66 degrees, lower(hypolimnion) 59 degrees. Thermocline no longer exists and turnover will occur. (if I remember right)

Winter water temps near bottom 4 degree C a yes though.

cube · #6 10-20-2014, 11:14 AM

Quote:

Originally Posted by RavYak

What is the wab temps now? 3 weeks ago it was still 8-9 degrees. I haven't been out there lately since you aren't supposed to use large hooks now.

The temp is 48 F or 8.9 C.

The lake will continue to mix and turn over until you have a thick inverted thermocline or you get stable ice. As shallow as Wabamun is it never gets a stable thermocline until after stable ice, and then it is an inverted thermocline.

greylynx · #7 10-20-2014, 11:53 AM

Dodgeboy is correct. 4 degrees is where water is most dense..grade 9 science. So the more dense the water is the more it will sink to equilibrium.

A lot of shallow lakes in Alberta do not stratify due to the constant churning action created by the wind.

But even in shallow lakes like LSL that are churned a lot by wind, one will discover a thermocline at about 10-12 feet in July and August.

tam474 · #8 10-20-2014, 01:01 PM

Dodgeboy is correct that water is most dense at 4 degrees but it does not control turnover

huntsfurfish is correct. The water temp does NOT have to reach 4 degrees before turnover. It has to do with relative density differences (delta rho) present within the water column. When delta rho is sufficient then turnover will occur

Each lak

YeeHaw · #9 10-20-2014, 08:24 PM

The water was 45 and came up to 48 in spots today. The lake has turned over judging by the weed floating and washed up on shore. Fish were scattered between 3-15 cow. Got one respectable fish at just under 15 lbs, couple 5lb, and a hand full of snot rockets.

Pinhead · #10 10-20-2014, 09:04 PM

Was out on Saturday, and it was slow but still got my biggest of the year. Did not weigh him but he was over 20 lbs. Man was he fat! Second biggest was around 12 lbs. We worked hard for them though, they were not scattered but in specific areas. They seemed to want access to the deeper water.

http://[URL=http://s125.photobucket.com/user/Pinhead338/media/CFC9DA86-F32E-4E6B-8106-86D93A7CB3EF.jpg.html]

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Moefoe · #11 10-21-2014, 03:34 AM

Quote:

Originally Posted by Pinhead

Was out on Saturday, and it was slow but still got my biggest of the year. Did not weigh him but he was over 20 lbs. Man was he fat! Second biggest was around 12 lbs. We worked hard for them though, they were not scattered but in specific areas. They seemed to want access to the deeper water.

http://[URL=http://s125.photobucket.com/user/Pinhead338/media/CFC9DA86-F32E-4E6B-8106-86D93A7CB3EF.jpg.html]

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Your he is most likely a she and if she is a she then she is beautiful...joking aside this little 2-3 week window every year does pose problems in a lake fishery every year, but having said that the fish you do catch are for the most part SLOBS!! Nice Northern!!

HunterDave · #12 10-21-2014, 10:07 AM

Quote:

Originally Posted by huntsfurfish

Pretty sure it doesnt need to get anywhere near that cold to turn over.

x2 I watch Lac Lanonne and Lac Ste Anne turn every year.....in the summer. Filled with algae one week and it's gone the next. Around here that's what we call turning over.