Temperature Trends

[RoLo]

WOW!

Ok but I have some questions....

Florida strain LMB. They live, for the most part, in lakes that average 6' deep at most. There are only a few waters in Fl that have over 30' depth and those are reclaimed phosphate pits or the occasional sink hole/spring. And the temperatures on the surface vary from (observed) low 60s to 90+.

1) How much temperature variance can you possibly have in 6'?

The greatest thermal variance is in the uppermost layer (epilimnion),

which could possibly range from the high 50s in the panhandle to nearly 100 deg in the Everglades.

In Canada the hypolimnion budget is 39 deg F but in Florida it's usually closer to 65 deg F.

2) If they do not move laterally and only vertically in the water column, can they actually get relief?

In my opinion, bass don't seek temperature change and don't understand relief, but most anglers take exception to my view.

When bass are shutdown by water climate, I picture them slowly losing altitude in the weed bed, finally ending up on the lake floor,

it's physiological. From all appearances, only time provides relief.

3) Is dissolved oxygen content not the most important factor affecting their location in the water column?

Under normal conditions, oxygen shouldn't be a problem and usually isn't.

About 25 years ago the fishing community went through an "oxygen meter" craze.

During that fad every article you picked up espoused the importance of dissolved oxygen content.

Like most crazes, that one too faded into oblivion. When a body of water is stressed by low oxygen content,

bass are forced to remain shallow, because deeper water contains less dissolved oxygen, not more.

4) What do they do when we have a 10* drop in surface water temperature in a 24 hour period. (sunshine showdown 08).

I don't know what they do, but I'll be home trying to recode my stock-timing model ;D

From what I've read and heard, there's no shortage of anglers

who can catch bass after a major cold-front, but I'm not one of them.

5) How does the barometric pressure figure into the equation? With a dramatic drop in air temperature cause by a severe cold front it is usually accompanied by a drop in the barometric pressure. How does this affect fish location?

In my view, barometric pressure is purely coincidental to other more important events (not a popular view).

Let's break it down: The difference between a normal barometer and a low barometer is about 0.77 lb / sq in.

If a bass moved just 1.8 ft upward in the water column, the drop in body pressure would be identical

to a major swing in barometric pressure. Somehow I can't force an interest in barometric activity.

Lois and I have hauled ling and whiting from water over 100 feet deep.

When they made it topside, their eyes were bulging out of their head and their stomachs were in their mouth.

Now THAT'S pressure

My ten largest fish in the last year all came out of 3-4 ft of water

For the natural lakes in Florida, your most productive depth range is right on the snot. But not if you were fishing the TVA impoundments.

8.3 in August, 10 am, clear blue sky, 85* water temp

If you asked me to guess, I'd have come pretty close.

I would've said between noon and 3 pm (max solar gain).

As for August, 85 deg and clear blue skies, that's a broken record

Lee, I'm mad, we've got a shootout in progress and my boat has been in the shop for 3 weeks.

I was supposed to pick it up today, and now it's Thursday. They finally read my work order and now I'm waiting for a livewell impellor. Whatever happened to service?

Roger

[Paul Roberts]

Nice post Paul,

We all learn from everyone else, but what we do with that mountain of data has a way dividing us into different camps.

I guess I don't see the separate camps.

I may be wrong, but I don't believe that it's 'sunlight' per se that spooks bass. On the contrary,  I believe that bass welcome sunlight because it enhances their vision underwater. Instinctively, bass probably sense that they too are more visible and tend to locate on the edge of shade peering over sunlit water. If catching bass is more difficult in sunlit water, that's testament to the fact that sunlight is a benefit to bass. Bass in clear sunlit water enjoy maximal vision and will react to everything they see. We call that behavior spooky,  but bass call it the cat's meow (we're at a disadvantage, not bass).

Agreed. Recognize though that I didn't say that sunlight spooks bass, only that the difficulty in catching them under bright sun could obscure an angler's interpretation of post frontal bass behavior.

Now, what might one do? Here are some good answers:

-Fish deep

-Fish heavy cover

-Fish slower

-Use light tackle

-Down-size

I agree with that entire list, and might only add the use of neutral colors, nothing gaudy.

But why are we toning down our delivery if sunlight is the culprit? Sunshine does not cause torpor or indifference, oppositely solar gain enhances the activity of sunfish (all life). On the other hand, a downtrend in water temperature can and will cause a downtrend in bass activity and bass disposition.

It is a matter of degrees, and a short-lived cold-front with a small temperature differential (difference in air temp and water temp) will barely affect bass even in shallow water. Conversely, bass in deep water (rare in my parts) won't be affected at all by most cold-fronts, save a prolonged cold-front with a sharp temperature disparity.

See above response.

Quote:

4) To say that "a bass is a bass" no matter where you are is invalid. As you would expect, the optimal temperature range for Florida-strain bass (75 to 85) is about 10 deg higher than the optimal range for a northern-strain bass (65 to 75).

This differential is the cause of many arguments.

GUILTY OF BIAS. I UNDERSTAND THIS, BUT HAVE NEVER SO MUCH AS SEEN A FLORIDA LARGEMOUTH. I'M WORKING WITH NORTHERNS AND TAKE POSSIBLE FLORIDANUS INFO INTO ACCOUNT -A SUBSET. IT WILL BE INTERESTING TO SEE WHAT OTHER DIFFERENCES/SIMILARITIES APPEAR. ONE THING I'VE READ IS THAT FLORIDANUS' RESPOND MUCH MORE NEGATIVELY TO COLD FRONTS THAN NORTHERNS, WHICH MAY REPRESENT MY NIT-PICKING OVER THE INTENSITY OF A GIVEN FRONT.

I was born in New Jersey and the lion's share of my bass fishing took place in Jersey, New York and Ontario.

I've also lived six years in Georgia and going on ten years in Florida.

Bottom line, I've been fortunate in being exposed to northern-strain, Florida-strain and intergrade bass.

Aside from the obvious difference in growth rate, there's a significant difference between the attitude and behavior

of northern-strain and Florida-strain bass, and it's not illusory, it's blatant.

I think I already responded to that one.

Quote:

5) Given adequate oxygen, Bass feel no discomfort in any water temperature, therfore they never have to relocate on the basis of water temperature.

I DON'T AGREE. FISH ARE KNOWN TO MOVE TO SEEK TEMPERATURE, AND I CAN SEE BOTH VERTICAL AND HORIZONTAL MOVEMENTS BEING A PART OF THIS IN A BASSES LIFE

I'm not at all surprised, because I'm pretty much on my own upholding this premise.

But just as you're from Missouri on the ramifications of a cold-front, I've yet to be convinced that fish experience any discomfort

stemming from water temperature alone. Human beings are warm-blooded animals and need to maintain a body temperature

of 98.6 deg F otherwise die. To warn us that we're getting out of safe range our body will produce discomfort (too hot or too cold).

In stark contrast, bass have no body temperature to maintain, so there's no need for a warning system that causes discomfort.

While ice-fishing on Budd Lake, New Jersey a yellow perch jumped out of the basin we shaved in the ice to store our caught fish.

When I finally noticed the perch it was apparently dead and frozen to the ice. I had to kick the fish a couple times to break the frozen hold.

To my amazement, about the 10 minutes later that perch was swimming in the basin,

looking none the worse for wear.

          However, when water temperatures reach an extreme they're usually accompanied by other phenomenon.

For instance, even though bass in coldwater may feel no discomfort, frigid water  temperatures reduce

their metabolism and digestion and depress their aggression, a time when a dead minnows may be more successful than a live minnow.

Torpor causes no discomfort, it's no more painful than slumber. At the opposite end of the spectrum is hot water,

and though it may not cause discomfort per se, warm water has a lower saturation point for dissolved oxygen.

In Florida at least, oxygen is usually not a problem in water under 90 degrees, in any case, oxygen-deprivation is a secondary stressor

exacerbated by warm water, but the warm water per se causes no discomfort.I'm not aware of any ichthyological study confirming the migration of bass triggered solely by thermal discomfort

that was totally unrelated to other stressors such as oxygen-deprivation.

I have read the results of poorly conducted studies that would leave the reader with that impression,

but none that you couldn't easily poke holes in.

I see, I think...Of course, temperature and oxygen are directly related. But whether it's temp alone or not is a pedagogical question, not a very practical one unless you can find very high temps with super-saturated water very highly unlikely, especially in largemouth waters. Thus upper temperature limits are valid measurements.

Of course DO is involved; It is integral. Not sure of your point. Can you provide a practical example why an angler might ignore temp measurements beyond the upper limits? I can think of one but it doesn't fit your argument.

But DO could potentially be very important at more normal temperatures,and this can be an issue for anglers. Temp alone would not provide this.

The disagreement centered on whether fish will move in response to temperature. And my response is, for all practical purposes: Yes, fish WILL MOVE to avoid high temp (and the always associated O2 depletion), and even to trim their metabolic requirements. There are plenty of studies demonstrating this.

I'll close with a little something I've learned about 25 years ago,

and it's done a pretty decent job of keeping me out of trouble.

It's founded on water temperature trend, but gives the angler a clue as to the current direction of that trend.

POSITIVE

Air temperature greater than the water temperature, regardless of the value in degrees.

NEGATIVE

Air temperature lower than the water temperature, regardless of the value in degrees.

Agreed, but for clarity for readers: This is valid only if enough time is allowed for water to give up or absorb the heat. Water is notoriously stingy with heat in both directions. Thus the need to look at trends over time, rather than the given temps at any one time.

Good closing, Roger!

[Paul Roberts]

In my view, barometric pressure is purely coincidental to other more important events (not a popular view).

Let's break it down: The difference between a normal barometer and a low barometer is about 0.77 lb / sq in.

If a bass moved just 1.8 ft upward in the water column, the drop in body pressure would be identical

to a major swing in barometric pressure. Somehow I can't force an interest in barometric activity.

Lois and I have hauled ling and whiting from water over 100 feet deep.

When they made it topside, their eyes were bulging out of their head and their stomachs were in their mouth.

Now THAT'S pressure Tongue

I have to comment:

BINGO!!! Nailed that one head on, Roger. Too much voodoo out there. (I can hear the Twilight Zone theme song now).

[RoLo]

Can you provide a practical example why an angler might ignore temp measurements beyond the upper limits? I can think of one but it doesn't fit your argument.

I'm not sure I understand your question.

As the water temperature rises, water becomes increasingly lighter and more porouos (less dense).

Eventually it will be unable to hold ample dissolved oxygen to support life, the cause of massive fishkills.

An oxygen-deprived bass is in big trouble, shows signs of stress,

and will die unless he finds water with at least 5 ppm.

My theory is this, if you could deliver 10 ppm O2 to that same bass,

you'd remove signs of stress and the bass would no longer be interested in altering its location.

Though I didn't mention it, there is an upper metabolic limit

beyond which basal rates are racing, like a person on amphetamines.

This I believe is the reason why bass living south of their natural range

die prematurely of thermal burnout, but that's a whole other ballgame.

Roger

[Catt]

WRB, that is not a personal attack ok, read what you wrote

Water temperature controls nearly every aspect of their lives

As long as the temperature is within the basses comfort zone, the DO levels are good, the PH is OK and food supply is there, the optimum temperature isn't a primary factor

The first statement says temperature controls a bass's life, the second statement says dissolved oxygen, PH, and food supply cancels temperature; exactly what Ken Cook stated. Ken's statement about shallow water was the fact that bass are shallow during spring and fall because that is where the food supply is not because of temperature. If the oxygen level or food source aint there it doesn't matter what the temperature is.

Paul; How do I deal with cold fronts? & brilliant blue skies

-Fish deep

-Fish heavy cover

-Fish slower

-Use light tackle

-Down-size

Agree except with the last two; I found after 35 years of fishing deep structure and heavy vegetation down sizing tackle and lures is not necessary.

Roger I think we went to the same school & had the same teacher  

All and all this is one outstanding post with some extremely valuable information contributed by everyone

[senile1]

Wow.  I saw this thread when it first started last Thursday.  I was out of town all weekend visiting my kids so I didn't look at it again until last night.  It had grown . . . . ever so slightly.  :  

It looks like everything has been said that could be said.  The reason bass react in particular ways is a great topic, but it is one that can become confusing to newer fishermen, especially with the differing opinions presented by knowledgeable fishermen.  I just want to reiterate something that Catt said earlier in one of his posts on this thread that ties all of this together for fishing purposes.

I still don't fully understand how natural variations in weather and seasons affect fish. Nobody really has all the answers. But based on my lifelong experience as a bass angler and biologist, I have a good understanding of where to find bass as the seasons change and as the water temperatures rise and fall.

We may disagree on what causes a bass to do what it does, or to choose certain locations, but as long as we know there will be bass at particular locations, under certain conditions, we can find them and catch them.  

[RoLo]

Roger I think we went to the same school & had the same teacher

I consider myself self-mentored, so if you can agree with most of what I believe,

you're obviously a graduate from the "School of Hard Knocks"

Roger

[Catt]

Roger I think we went to the same school & had the same teacher

I consider myself self-mentored, so if you can agree with most of what I believe,

you're obviously a graduate from the "School of Hard Knocks"

Roger

Yelp still got a few bruises  

[WRB]

WRB, that is not a personal attack ok, read what you wrote

Water temperature controls nearly every aspect of their lives

As long as the temperature is within the basses comfort zone, the DO levels are good, the PH is OK and food supply is there, the optimum temperature isn't a primary factor

Let me try to clarify the statement one more time. Bass are cold blooded animals and their existance is dependant on water temperature, that is a major factor. Once the water temperature is within their preferred temperature range, then it becomes less of a factor. Food and sancturary becomes the basses primary concern because the water temperature is warm and stable, their metabolism demands increase to eat more and rest. If for whatever reason the stable warm water temperature change dramtically, more than 10 degrees, then the bass will relocate. The summer temps are normally stable for several months, when the they change and become unstable agian, water temperature will become a major factor, until the season's return annually to the summer warm water period once agian.

WRB

The first statement says temperature controls a bass's life, the second statement says dissolved oxygen, PH, and food supply cancels temperature; exactly what Ken Cook stated. Ken's statement about shallow water was the fact that bass are shallow during spring and fall because that is where the food supply is not because of temperature. If the oxygen level or food source aint there it doesn't matter what the temperature is.

Paul; How do I deal with cold fronts? & brilliant blue skies

-Fish deep

-Fish heavy cover

-Fish slower

-Use light tackle

-Down-size

Agree except with the last two; I found after 35 years of fishing deep structure and heavy vegetation down sizing tackle and lures is not necessary.

Roger I think we went to the same school & had the same teacher

All and all this is one outstanding post with some extremely valuable information contributed by everyone

I haven't chipped in on frontal conditions up to this point.

Barometric pressure affects on bass are misunderstood, IMO. The most severe storms, for example only change the atmosphic presseure about 100 millibars. Humans feel astmosphic changes more than bass do and tend to apply the pressure changes to how they feel.

Consider a 100 millibar pressure change affect on the water surface; it equals about 3 inch of water added weight to the bass. Yes they feel the change, but I don't believe the pressure change has a major impact. What does have an major impact is the change in light intensity due the increased, then decreased moisture in the atmosphere. Low pressure forms a depression the moist air moves into and that triggers activity as the eccosystem becomes more active. The low pressure is pushed out by a frontal high pressure, winds increase, the moisture is push out and the atmosphere becomes extremely clear, increasing the light intesity. The astospheric changes from claim moist conditions to clear windy conditions has a dramatic affect on the shallow water eccosystem.

Everyone has frontal conditions from time to time. The lowland lakes and reserviors that are shallow are affected more than the deeper highland and hill land type reserviors becuase the light intensity changes and wind affects are more dramatic. Where I live and fish it is easier to move to deepr water where the climatic changes have less impact, so that is what I do; fish deepr water. In a shallow water enviroment, like Florida for example, you must try to locate active bass and they aren't too active after feeding during the low pressure system. The bright sky conditions usually cause the bass to seek sancturary under cover in shallow water, so that is the best place to start; near or in the cover with presentations that target inactive bass.

WRB

[FD.]

Roger, if you don't get your boat back soon I still have my 17.5 triton for sale in the yard if you need to borrow it.

[RoLo]

Roger, if you don't get your boat back soon I still have my 17.5 triton for sale in the yard if you need to borrow it.

Unless you're pulling my leg, that's one heck of an offer Lee!

Actually I just spoke with Mickie today (Hoppys Marine) and unless he encounters yet another snag, I'll be picking her up tomorrow.

I can't believe you're selling your boat  :-?

Roger

[fragelicious]

On 3/28/2008 at 12:00 PM, RoLo said:

There's no doubt about it. As I've posted here many times, I believe that the "trend" of water temperature

is exponentially more significant than the static "numeric" value.

If someone tells you the water temperature is 65 degrees, they haven't told you very much.

Provided you have your own water temperature gauge, you'd be far better informed if you were told

what the water temperature was two-days ago. If it was 60-deg two-days ago, that's a positive condition (uptrend),

but if it was 70-deg two-days, that's a negative condition (downtrend).

Dean Rojas set the all-time BASS one-day record on Lake Toho.

He did so during a powerful warming trend that followed a bitter cold-front...no surprise there.

My boat's been in the shop almost two-weeks now, but I posted the modest results of our last trip (Southeast section).

There was a stiff wind out of the north, and we were working the northern shore (protected side).

It was beginning to look like a blank, so I ran to the south side in search of "rising" water temperatures.

I figured the warmer upper layer (epilimnion) was blowing southward, so it might improve our situation.

Sure enough, we made fish contact in the choppy water and whitecaps along the south side. Here's the irony,

windblown plankton usually gets the credit, but the real reason was rapidly rising water temperatures.

During a stiff wind, the whole lake rotates like a giant waterwheel. As the top layer blows south,

the water on the north side is replaced by cold water siphoned from the deep. The differential was 6 degrees,

which indicates the magnitude of the uptrend on the south shore, and the magnitude of the downtrend on the north shore (3 deg x 2).

Roger

You nailed exactly my spring weather strat. Warming trends fluctuate and the bites pick up closer to the end of them. Then start over after the next front. Excellent stuff. North shore's need big wind from the south to activate. Just like you said north winds pull up cold water from the deeper areas this time of year. Good stuff brother.