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fishhead
11-16-2010, 10:57 AM
what would be the consensus on best water temp for feeding trout ? seems I'm always early in the season or late ! wild trout in particular, as I have had some spectacular days on hatchery fish when I could barely feel my hands and continually cleaning ice from guides. I know this is open to specualtion, and I am talking about water temps not air temps.
thanks Fishhead

MadisonBoats
11-16-2010, 01:02 PM
I think it basically relies on what is the predominant food source at the moment. I carry a small seine to help me identify the patterns and colors. This can change hourly and it usually related to light, weather, and moon phases:biggrin:. I find that it takes a couple hours longer for fish to rise on sunny days in the winter than in the summer.

Here is a good opinionated article about water temperatures. I underlined some key points in the article.

CITE:
Water temperature and trout feeding habits
Are the textbooks right? On-stream experience indicates "no"
by Clive Schaupmeyer (Adapted from The Essential Guide to Fly-Fishing by the author)



Trout feed when there is food to be eaten. The amount they eat depends, of course, on their size, availability of food, and on water temperature. Water temperature affects their metabolic rate and desire or need for food. And presumably their eating habits depend on things we don't understand. Temperature is certainly something that we should not get too anal about ... but still it's interesting.

According to many sources, each species of trout has an ideal temperature range in which it feeds the heaviest. But this is likely of more academic interest than practical use to most of us out for the day or away on vacation. If you've just driven across two provinces (or three states) to fish in a famous river and the water temperature is outside of the reported ideal range what are you going to do? Drive home? No. You are going to fish and make the best of it. Perhaps the temperature may explain why we are not hammering them, but what's the sense in moaning about it - eh?

A few years ago I met a man from Rhode Island sitting on a bridge crossing the North Raven River in central Alberta. He was eating a cigar (yes, eating the cigar) and generally taking it easy while waiting for his partner to come off the stream. I had just stopped by the stream to kill an hour or two in the afternoon while waiting for the main event later that evening on another nearby river. (This was the afternoon matinee. Tonight was the full-length feature.)

Neither of us had caught fish in the couple of hours we were both on the water. It was a nice day. He was heading elsewhere the next day and I was anticipating the night shift. We were happy as clams.

Out of the willow-tangled meadows emerged a local angler all bedecked in the latest gear - right out of the catalogues. He inquired how we had faired and then told us he had caught only seven browns and the fish were decidedly off compared to a few days before when he had caught many more. He told us the water temperature was way down and well below the ideal brown trout range and he might as well go home. Clearly not an option for the cigar eater or me.

The survival range for trout is published at 35 to 75 °F (2 to 23 °C). And the optimum feeding range for most trout species is between about 50 and 68 °F (10 to 20 °C). Cutthroats and brook trout feed optimally at slightly cooler temperatures.
http://flyanglersonline.com/features/canada/can10.jpg
I am doubtful about the reported optimum feeding temperature ranges for trout. On-stream experience does not support the 'facts.' My brother, Gary, has a theory about feeding and temperature: the trend in temperature direction is more important than the actual temperature. At the lower range, he thinks that the exact water temperature is not as important as whether it's getting warmer or colder. If the stream temperature rises from 45 to 50 °F (7 to 10 °C), the trout will get jazzed and increase feeding - perhaps not as aggressively as they might at, say, 60 °F. But if the temperature drops from 55 down to 50 °F (13 to 10 °C) they will go off their feed. So you could have two identical water temperatures in the same creek, perhaps two or three days apart, and the feeding habits could be totally different. It depends on whether the water is getting warmer or colder.

Of course this is complicated by the relative insect activity as well. The bugs may also be turned off by falling water temperatures and therefore will not be as active. So, does trout feeding increase (as the temperature goes up) because they get hungry? Or because there is simply more bug activity?

Gary's theory may or may not be so, but on-stream experience seems to bear this out - sometimes. Trout feed better when the temperature is on the upswing (at the lower range) than they do when the water temperature is falling.

Higher temperatures definitely cause feeding activity to drop off. Trout fishing at lower elevations (and in southern latitudes) can be quite poor when there is a long hot spell. If the water temperature gets too high, the dissolved oxygen content can fall to fatal levels.

There's a final issue about the published temperature and activity ranges for trout. They just don't hold true at the lower end. They imply that trout simply will not eat when the water temperature hovers just above freezing. So why then are we able to catch trout in western streams from November through March when the water temperature is a degree or so above freezing? Sure the fish are sluggish, but they do eat our flies, and I have seen rainbows actually chase nymphs in ice-cold water. (And of course, the reference I found - stating the minimum temperature for survival is 35 °F - is simply wrong. River water can be supercooled to a half degree or so below freezing. The fish are sluggish, but they don't die.)

It gets more interesting yet. Hourly catch rates in winter when the water temperature is barely above freezing are often higher than in spring and summer. Go figure.

Closing thought .. .The friend you lie for has a liar as a friend.

JohnH0802
11-16-2010, 01:21 PM
Shawn,
A great article that I enjoyed. I have not thought about the temperature issue too much when it comes to trout fishing....mostly because I don't get to go enough for it really to matter. About the closest I get to checking the temperature is trying to plan a trip at a time when the odds are in favor of at least some favorable weather.

I have noted some temperature issues with redfishing though. I have found that in the winter, when it has been cold, that a small temperature increase can really turn the redfish on...the temp is not what appears to be the issue, but the increase. I have had some pretty good days when the water warmed up only a couple of degrees.

I have also seen the same in tailing fish....have caught some in November on a high tide after I had stopped seeing them tail. Had a warm front come in and decided to stop by a flat to see if the warm spell had them back on the high tide flat and it did. I caught 5 or 6 on high tides last November in 2 days of fishing.

John

kentuckytroutbum
11-16-2010, 01:29 PM
Shawn-

Kind of makes you wonder if our preconceived "science" about feeding habits is all wet, and needs to be re-evaluated.

Bill

MadisonBoats
11-16-2010, 03:43 PM
.....I have noted some temperature issues with redfishing though. I have found that in the winter, when it has been cold, that a small temperature increase can really turn the redfish on...the temp is not what appears to be the issue, but the increase. I have had some pretty good days when the water warmed up only a couple of degrees.....

John, Do you think that activity could be more related to barometric changes? I have been charting this in my fishing log and this is something that I have found very interesting.

Note:
http://www.quickoneplus.com/fish/articles/page.asp?page=barometric
Tracking:
http://weather.gladstonefamily.net/qchart/C6625?date=20101107
Shawn-

Kind of makes you wonder if our preconceived "science" about feeding habits is all wet, and needs to be re-evaluated.

Bill
Bill, I think this issue is too vast and too diverse to clarify with a simple philosophy. However, I think it is much easier to work at a stream/river level to understand feeding habits. I believe the feeding habits are diverse from comparing the TN streams and tail-waters alone. I enjoy this information not so much in how it relates to fly fishing; but, more in learning how nature is affected by different conditions.

fishhead
11-16-2010, 04:01 PM
Thanks for the replies, very interesting article. I seem to always be able to get time off to go fishing when temps are dropping. I will moniter stream temps closely next week and see how rising daytime temps effect the water temps and fishing. or vise versa.
always more to learn.
thanks Fishhead

kentuckytroutbum
11-16-2010, 04:07 PM
John & Shawn-

I'm agreeing with you both. My comment was regarding so-called "old wives" tales that seem to keep getting repeated, such as spring or neap tides, sunny vs cloudy, warm vs cold, etc.

I strongly agree with John regarding warm & cold fronts as it relates to saltwater flats, and also stream fishing. I've noticed that a low pressure system, and related colder temps stop the fish from feeding. After it passes, the fishing seems to pick back up. I've always wondered how fish sense the approach of a low/cold front when they're in an incompressable liquid. What tells them that ?

Perhaps fish are just opportunistic predators that feed together for a while, and then cease for a while. Maybe one fish feeding stimulates the other fish to feed such as "I'm going to get mine before the other guy does." I don't know.

But I do appreciate your posted articles as it stimulates me to think about the factors that affect fishing. :cool:

Bill

JohnH0802
11-16-2010, 04:36 PM
Shawn,
I have not really done a good job of keeping barometric pressure information on my during my redfishing to know....I do know that some of my best fishing days fishing for largemouth bass have come just prior to a storm, and some of my worst were post front.

On some of the days that I know of specifically, it was just a warming trend that lasted long enough to raise the water temp without the presence of a storm. I know that one of the days last November was as a front was coming in after several warming days...it was raining while I fished that high tide.

I had to talk my fishing partner into fishing that day, because he saw the rain coming. We ended up catching two reds each that day. I will have to ponder this some more and pay more attention to the barometer when it comes to redfishing.

Bill,
As far as what tells the fish that a low/high pressure system is coming, I am not sure. I do know that when you have high pressure you can sometimes see that a river is flater than normal....

John

silvercreek
11-16-2010, 04:46 PM
John, I've also wondered how they can detct a pressure change. Maybe it is detected by the swim bladder or the lateral line which is very sensitive. These things are a mystery that more than one angler has pondered. Regards, Silvercreek

NDuncan
11-16-2010, 04:48 PM
I've always wondered how fish sense the approach of a low/cold front when they're in an incompressable liquid. What tells them that ?


I wonder if it has a noticeable effect on their air bladders?

elkhaircaddis
11-25-2010, 12:35 AM
i know the fish in the park are extremely hard to catch when the water temp on this website is anywhere near 40 or below. Usually if byron temps the swinging bridge, i get 6 degrees cooler halfway up tremont. If its below 40 where you are standing, fish will be extremely difficult to catch. Im sure they can be caught, but not many and not often. Now if i am on a tailwater or DH or something with stockers, cold temps are not much of a factor. I can remember one day when it was 13 degrees (air temp obviously) standing on the bank of the little tennessee river and pulling trout in one after another. I also like fishing the clinch much better in the winter, there are fish rising everywhere most of the time. But constant water temps and trucks full of fish can have that effect...

Knothead
11-25-2010, 09:05 AM
There are a lot of variables in the life of a fish. I have seen times that, before a front, bass turned on so you had to go behind a tree to change lures. When the front hit, they shut down with a bad case of lockjaw. It would be interesting if one kept a journal with air and water temps, BP, wind direction, etc. just to see what combination proved the best.

flyman
12-04-2010, 01:07 AM
Once the water temps fall below the low 40's I just don't fair very well, but I'll admit I don't fish much any more when it gets that cold either.:cool:

MadisonBoats
12-04-2010, 10:34 AM
I think Winter fishing is one of my favorite times to fish. The air is usually more dense and insulates the river valley very well. The sounds and nature of the water changes. It is very interesting if you stop and pay attention. I find it odd reaching in to the water and it is warmer than the air.:smile:

*However, the cold plays havoc on my leaders and tippet. They like to break and kink on me...

LA MantaRay12
12-05-2010, 10:21 AM
Seeing all the discussion around barometric pressure and its affects on fish and fishing has been very interesting.

I would have to believe that just like any pressure column, when barometric pressure is increased that pressing down on the water column, which is a non-compressable fluid, transmits the pressure change almost directly throughout the waterbody and that a fish would be able to identify small changes whether through its air bladder or lateral lines.

These pressure changes in the atmosphere are not that undetectable via human body function...just ask anyone with an arthritic knee or sinus infection. Small pressure changes affect them as well....why not a fish whose level of detection is so much greater than ours.

Temperature like anything else plays a part but i agree with the change of temp being of greater significant factor over the actual temperature until you get below ~ 40F....when its frigid outside would you rather be buried in your favorite sweatsuit next to a warm spot or out in the elements. Same for a fish....when water temps drop they huddle into a relatively warm or more stable position (deeper is more constant) but when small "warming" trends takes place, just like you and I, they look to move and take advantage of the increase in temperature and activity that will come with it.

my two cents...which is really worth about 1/2 cent with inflation.

Charles

MadisonBoats
12-05-2010, 10:50 AM
Seeing all the discussion around barometric pressure and its affects on fish and fishing has been very interesting.

I would have to believe that just like any pressure column, when barometric pressure is increased that pressing down on the water column, which is a non-compressable fluid, transmits the pressure change almost directly throughout the waterbody and that a fish would be able to identify small changes whether through its air bladder or lateral lines.

These pressure changes in the atmosphere are not that undetectable via human body function...just ask anyone with an arthritic knee or sinus infection. Small pressure changes affect them as well....why not a fish whose level of detection is so much greater than ours.

Temperature like anything else plays a part but i agree with the change of temp being of greater significant factor over the actual temperature until you get below ~ 40F....when its frigid outside would you rather be buried in your favorite sweatsuit next to a warm spot or out in the elements. Same for a fish....when water temps drop they huddle into a relatively warm or more stable position (deeper is more constant) but when small "warming" trends takes place, just like you and I, they look to move and take advantage of the increase in temperature and activity that will come with it.

my two cents...which is really worth about 1/2 cent with inflation.

Charles

Great post and interpretation of your thoughts. However; water is compressible and becomes more dense from around 40 degrees towards 32 degrees and then the magic happens. Around 33-31 degrees water reverses properties; well, in a layman's explanation. I have a link in one of my posts about this subject. It is very interesting and one that I never realized.

Barometric pressure has a huge effect on shallow water bodies more so than in deep water. Also, this effect is exaggerated by water/air temperature changes due to the density of the air/water.......

LA MantaRay12
12-05-2010, 11:14 PM
Good point MadisonBoats...

As the water temp falls it does become more dense as long as it is liquid to about 4oC at which point its density reverses. Then, as it takes on its crystalline structure (ice) it then expands and its density quickly degrades. It is true, water is compressible, but the amount is almost insignificant. Due to the polarity of water molecules they are held very tightly togther and there is not much room for compression of molecules. This is also the phenomenon behind surface tension.

compressibility of water is small. An increase of pressure by 1 atmosphere (= 1013mbar = 14.7 psi) causes a decrease of the water volume by 5.3*10-5 of the original volume.

http://hypertextbook.com/facts/2007/AllenMa/wikipedia.png
Great discussion...This is really a super forum.

MadisonBoats
12-06-2010, 10:19 AM
Good point MadisonBoats...

As the water temp falls it does become more dense as long as it is liquid to about 4oC at which point its density reverses. Then, as it takes on its crystalline structure (ice) it then expands and its density quickly degrades. It is true, water is compressible, but the amount is almost insignificant. Due to the polarity of water molecules they are held very tightly togther and there is not much room for compression of molecules. This is also the phenomenon behind surface tension.

compressibility of water is small. An increase of pressure by 1 atmosphere (= 1013mbar = 14.7 psi) causes a decrease of the water volume by 5.3*10-5 of the original volume.

Great discussion...This is really a super forum.

Sir, I hope you did not consider my reply as condescending. I am appreciative of your input and I enjoy learning and discussing topics like this one. Your explanation was much better than what I tried to convey:smile:. Good Job!

I have been studying barometric pressure effects on fly fishing for the past year and I started recording it in my log book. One of the best websites for getting information post-trip is:http://weather.gladstonefamily.net/qchart/C6625?date=20101107

I use this website to more-accurately track my fishing trips with temperature and barometric changes. I think the link I sent you is for my location...After each of my trips; I will visit the website and complete my conditions log based on the time I fished. You might find it interesting; just change it to your location.

Great discussion LA MantaRay12 and I enjoy your contributions!

LA MantaRay12
12-06-2010, 10:00 PM
MadisonBoats....absolutely not, I do not see your response as condescending.... :smile:. I truly appreciate the level of intelligence i read in this forum. You for one have gone above and beyond to address my questions and those of many others.

I was really glad to see your response and look forward to future opportunities of continued learning. Thank you very much for the website address...i have been looking for a GOOD site to obtain information on conditions while i fish. I too keep a journal and look forward to one day sharing, face to face with anyone in this forum, it contents.

I really enjoy this incredible sport and get greater joy out of helping others by providing my successful fishing spots and techniques. I have so much to learn and spend hours reading information the members of this forum provide.

I look forward to future discussions. Unfortunately i tend to be very technical...just my nature...being an engineer and all.... :rolleyes:

My only regret is that i did not get to meet any of you all while in the Smokies this past Thanksgiving. We visit there every Thanksgiving and I hope to begin in 2011 making an annual trip in the Spring.

Tight lines and safe wading to you all....

Charles

MadisonBoats
12-07-2010, 10:44 AM
.....
I really enjoy this incredible sport and get greater joy out of helping others by providing my successful fishing spots and techniques. I have so much to learn and spend hours reading information the members of this forum provide.
You and I share very similar fly fishing philosophies!:smile:
I look forward to future discussions. Unfortunately i tend to be very technical...just my nature...being an engineer and all.... :rolleyes:...Charles
I suffer from a similar trait. I guess it is my inquisitive spirit and my curious nature....However; this trait is one of the root characteristics about fly fishing that I enjoy. It can be as simple as you want it to be or as complicated as you make it. I believe that we all pursue it for a different reason and all the really matters is that we enjoy it!

flyaddict
12-08-2010, 02:55 AM
I read this article a while ago and when I saw this thread I thought I would dig it up and post it for you guys. I have fished all my life and swore by the barometer but this guy makes a good case.

http://www.midcurrent.com/articles/science/ross_pressure_myth.aspx

MadisonBoats
12-08-2010, 10:45 AM
I read this article a while ago and when I saw this thread I thought I would dig it up and post it for you guys. I have fished all my life and swore by the barometer but this guy makes a good case.

http://www.midcurrent.com/articles/science/ross_pressure_myth.aspx

This guy makes some great/supported points; however, I believe most of his information is directed towards saltwater fish and he is considering a completely different type of biosphere than those of 'cold-water' trout.

Most trout fishing is in shallow water and I believe the atmospheric pressure has a (compounding) effect on fish. Remember; they have super sensitive sensors on their body and their ability to sense change is very keen. His discussion of how minute the change scale of measurable pressure is kind of misleading. Think about it; look how much weather changes in that range. You can have clear conditions or a violent hurricane/tornado at each end of this fine scale.

I believe he makes valid points in his article. However; I think we have to address this idea by separating each habitat and species to better understand its effects. Thanks for sharing...

By the way; I am not scientist and I am just giving my opinion. It would be nice to find an article/study from a scientist that is based on the trout environment.

jeffnles1
12-08-2010, 12:46 PM
This has been quite an interesting discussion. Thanks all.

I have no answers, only questions.

I live in Northern Kentucky so most of my fishing is for warm water species (bass, bluegill, crappie, various panfish, etc.).

Regarding water temps from a cold front: I tested a couple times last summer when a front blew through ( a rare thing here last summer where it was just hot and then more hot).

Here is what I found: At the surface, after a noticable drop in outside temps, the next day, I found a couple degree difference with cooler water. However, when I dropped my thermometer in about 5' of water (the length of line I had attached to it) I didn't read any difference in water temp. Mind you, this is a little Fishpond stream thermometer I'm using and it doesn't read in tenths of a degree but all the same, no difference than I could notice. I hope this can add to the discussion.

I have no idea how fish can sense weather changes. Perhaps it's a combination of a lot of variables, waves on the surface, water temp, barametric pressure and light.

I've often wondered how big a part light played in it. However, I've tried night fishing after a front blew through and even after dark, there was a noticable difference in the number of strikes to number of casts ratio.

Unfortunately, fish can't tall. :smile:

Regardless, this has been an enjoyable thread for sure.
Jeff