Bass fishing predictions for next week

[Jim]

Hi all,

As some of you know and have helped with, I have been developing a model of Old Hickory lake for the last few years. The model includes a hydrodynamic model (water depth, current, dam discharge, water temperature, etc.), environmental model (weather, wind, moon phase, etc.), habitat model (habitat types, bottom substrate, lake sections, etc.). The lake model is then coupled with a fisheries model (species, seasonal requirements, TWRA catch statistics, etc.) to estimate the amount and location of suitable habitat. The main species are largemouth bass, smallmouth bass, white crappie, black crappie, bluegill, channel catfish, and striped bass.

Well, the predictions are starting to come out of the model. I have a version for Largemouth bass running and the crappie should be running soon. So I figured I would see if the modeled predictions are anything like what you all are seeing while fishing.

Based on the last ten years of data, the longterm coldest water temperatures are found on Feb 5 and 6. The lake and fish are in winter patterns for sure. By Feb 26, a solid 5 degree water temperature rise has occurred and the fish should be reacting and moving into their early spring coldwater patterns. By March 28, the lake has warmed enough to see bass begin prespawn patterns and the onset of the early spawning should be around May 6 with the lake averaging 64 degrees. Spawning should peak in late May or early June and be over by June 18.

Those are the average conditions but as you know it can be a warm or cold year compared to average. Right now the main channel of the lake is predicted to be around 38 (Army Corps reports 37 at Rockland). The large creeks should be colder and the shallows colder yet due to cold temps and snow melt.

I ran the predictions with the next 10-day weather forecast to see if the warm spell would have an effect. Here is the results:

1. We are still in a winter fish pattern and will be through next week. So focus on winter bass habitat and fishing patterns. Main lake is warmer than the creeks.

2. By next Wednesday (Feb 16) the whole lake should be about the same temperature.

3. By late next week, shallow protected coves with northeast orientations could see a 10 degree warm up. Look for places where the wind can not blow all the water out to mix with the main channel. Bad weather or rain could wipe this out.

4. Because the fish are still in winter pattern, if the warm up occurs, find the protected shallows nearest your best winter spots. This is only the first warming pattern of the year so it will take some time for many fish to react and move shallow.

5. the past 10 years of creel survey information by TWRA suggests that Area 2 (from the powerlines downstream of Spencer and Station Camp Creeks to just below Bledsoe Creek) has the highest catch rate of .78 bass/hour followed by Area 1 (dam to powerlines) with .64 bass/hr. This may be an result of the warm water from the Gallatin Stream Plant in Area 2.

6. The lower lake (Drake's creek especially) warms up faster and prespawn catch rates are much higher than in the rest of the lake (1.3 fish/ hr in Area 1 during prespawn compared to .88 fish/hr in Area 2). So if the warming trend holds for a few weeks expect Drake's creek fishing to pick up fast.

7. This is just for Largemouth bass. Smallmouth do something totally different as they spawn much earlier in the year.

8. I am really interested in the crappie models as they move earlier than Largemouth. I will report that as it get the results.

So, if you all see anything to support or refute these predictions, I would be glad to hear about it. Also, this is based on the 10-day weather forecast and we all know how much that can change. So if it is snowing late next week, don't blame me

Hope it helps,
Jim

[Travis C.]

Originally Posted by Jim

So if it is snowing late next week, don't blame me

Hope it helps,
Jim

Now that you have said that Jim, it better not or you may get a little round red smiley.




Thanks for the information, you sure do a great job with it.

[whrizob]

wow! mr. jim your program is incredible. you stated fact that has taken me all my life to learn, and bam! just like that you have the information! thanks for sharing this info! everyone should really apreciate what you just told them, bc you just eliminated a large part of the water that dont hold fish! i will let you know how we do this weekend. see alot people dont know that the lower end of the lake warms up faster. they assume that the upper end, being shallower warms up faster. but i have learned from fishing tournaments that the lower end does warm up faster and usually has some of the first spawning fish. but your right, the north facing creeks are the key! even north facing coves or pockets can be really good! i do have one thing to add. kinda of a question? in my experince, i know the main lake channel is warmer than the creeks; but i have better luck in the winter on the creek channel bluffs and sharp drops. does the program show that to be a productive place to fish? thanks mr. jim!

[Buccaneer]

Ok Jim just cut to the chase. Post the GPS waypoints, or you can PM me, and I'll report back with my findings. I plan to arm myself with your program (when available) and an HB Side Imaging unit. Problem is I will be motoring around looking at stuff and never fishing.

[Fishmanjoe]

Sounds like a great program, Jim! I hope somebody will do this for Percy Priest. I hope the program works out for you.

Buccaneer you don't want the side imaging its horrible it takes away all your fishing time and for personal experiance will almost make you drive into a boat dock cause your not watching where you are going I have one of the older 997 and its great. If you do get one pay close attention to the transducer mounting as it really affects how well it does/does not work. everyone will tell you level the boat trailer when you mount it and mount the ducer level also but this is a tab bit incorrect. it needs to be slightly angled up as boat are not level in the water

[Jim]

Originally Posted by Buccaneer

Ok Jim just cut to the chase. Post the GPS waypoints, or you can PM me, and I'll report back with my findings. I plan to arm myself with your program (when available) and an HB Side Imaging unit. Problem is I will be motoring around looking at stuff and never fishing.

GPS waypoints will be available soon. I am still fiddling with the best way to output them so they will be useful to you all.

Right now I can get them into Google earth or google maps so you and see the spots on your computer, but am working on getting them in a file format for hummingbird and lowrance units. That is not as simple, but hopefully will be solved soon.

Hopefully real soon I can get you some test locations to see if they hold fish.

Take care,
Jim

[Jim]

Originally Posted by Fishmanjoe

Sounds like a great program, Jim! I hope somebody will do this for Percy Priest. I hope the program works out for you.

Percy Priest is in the works. Maybe 60% done. Old Hickory is the test case and once it is all working with the bugs fixed, Percy Priest should be quickly available.

[Jim]

Originally Posted by whrizob

wow! mr. jim your program is incredible. you stated fact that has taken me all my life to learn, and bam! just like that you have the information! thanks for sharing this info! everyone should really apreciate what you just told them, bc you just eliminated a large part of the water that dont hold fish! i will let you know how we do this weekend. see alot people dont know that the lower end of the lake warms up faster. they assume that the upper end, being shallower warms up faster. but i have learned from fishing tournaments that the lower end does warm up faster and usually has some of the first spawning fish. but your right, the north facing creeks are the key! even north facing coves or pockets can be really good! i do have one thing to add. kinda of a question? in my experince, i know the main lake channel is warmer than the creeks; but i have better luck in the winter on the creek channel bluffs and sharp drops. does the program show that to be a productive place to fish? thanks mr. jim!

Thanks for the nice comments Whirzob You definitely know the Old Hickory bass. I wish I could catch them like you do.

A couple comments to further expand on your points.

1. Most lakes and reservoirs warm in the shallow upper reaches first. Old hickory is a run-of-the-river reservoir so there is high flow through with the upper reaches being very river-like. Additionally, Cordell Hull releases cool water and Center Hill Dam releases cold water (hence the Caney Fork trout fishery). This water has to warm up as it travel down the lake. High discharge can really cool the main channel in Old Hickory. The main creeks almost act like separate lakes. The upper and protected sections will warm faster. Drake's creek is the biggest embayment with lots of shallow water and thus can warm and not mix with the main channel.

In Percy Priest, the upper sections would warm first. but not for Old Hickory, Cordell Hull, Cheatam, or Barkley. It doesn't mean fishing isn't good in the upper sections, just not good for early spawning largemouth bass. Whites, striper, and big blue catfish move upstream in the spring and those can be the best sections to find them.

2. About your winter bass location question. You are right on target with their winter habitat. Not all bass move to the main channel. In fact many fish live in a relatively small range throughout the year, but some definitely travel. The individual fish can not tell if it is warmer or colder in the main channel than in the main creeks. It is only important what the water temp is where they live. Water temp is only one factor in locating the fish. For largemouth, strong current and cold water are not great combinations, so the bass need good current breaks in the main channel. This is less important in the creeks where the current is not as strong.

Winter water temp is more about stability. The main channel changes slowly so the fish don't react as strongly to weather changes. The main creeks change temp more quickly so the bass will respond to good weather or bad weather more strongly. Fish in protected shallows will react the strongest to weather changes. This is why fishing for shallow bass is always more hit or miss than fishing deeper big water structure. If conditions are right, you can really catch them shallow, but most of the time conditions are not "right". Thus, the "You should have been here yesterday, they were really biting" comment. If you chase the reports of a shallow water bite, you are usually too late as the conditions can change fast. Once you find bass on deeper structure, it can be more consistent until a major shift in the weather happens.

Take care,
Jim

[Travis C.]

Just add to or expand a little on the water temps from my experience as well. Most people think the water has to be in the upper 50's to mid 60's before you can fish anything like cranks, lipless or any moderately fast moving bait. Water temp in my opinion is an over-rated factor unless it is directly relating to the spawn. I have caught bass in shallow water on crankbaits in the low 40's and on the flip side in water above 90. You want water temp to be a factor you consider but what you want to look for is a "change" in temp.

Don't be afraid to pick up those shallow crankbaits or lipless bait and search for them like you would in the pre-spawn. It is not a jig or big worm only time of year. Once you find them then you can focus in on your drop-shot, shaky or jig if you want.

Also, you can put on a bigger crankbait like a DD-22 or DD Fat Rap and put the bait on the bottom then crawl it. They are so bulky that you can really slow them down but still cover water effectively. Plus, they will off a big meal for that fish who don't want to move very fast or far for a bite.

[Fishmanjoe]

Sounds like you have a real money maker there, Jim. Test it out and get a patent on that thing.

[Fishaholic]

Jim utterly incredible can't wait for the next round of testing

[Jim]

Originally Posted by Travis C.

Just add to or expand a little on the water temps from my experience as well. Most people think the water has to be in the upper 50's to mid 60's before you can fish anything like cranks, lipless or any moderately fast moving bait. Water temp in my opinion is an over-rated factor unless it is directly relating to the spawn. I have caught bass in shallow water on crankbaits in the low 40's and on the flip side in water above 90. You want water temp to be a factor you consider but what you want to look for is a "change" in temp.

Don't be afraid to pick up those shallow crankbaits or lipless bait and search for them like you would in the pre-spawn. It is not a jig or big worm only time of year. Once you find them then you can focus in on your drop-shot, shaky or jig if you want.

Also, you can put on a bigger crankbait like a DD-22 or DD Fat Rap and put the bait on the bottom then crawl it. They are so bulky that you can really slow them down but still cover water effectively. Plus, they will off a big meal for that fish who don't want to move very fast or far for a bite.

Great point Travis!

Your post made me think....so I went back to the models and data to see if temperature "change" idea was true. I am using the TWRA creel survey information from 2001 to 2009 for all lakes in TN and all of my model predictions to estimate environmental conditions (in this case water temps for the 7 day prior to the creel survey). There are almost 30,000 interview of bass anglers so the results are pretty strong.

Here are the results:

For Water Temperature stability (or the total amount of change up or down over the prior week) there is a strong relationship between stability and catch rates for largemouth bass.



You can definitely see that catch rates are higher when the past weeks weather has been stable.

Well, what about the trend in water temperature? Is it better to have cooling, stable, of warming water temperature?

Again from the same dataset, stable temps are better than cooling or warming waters.



This surprised me a little as I alway like to see warming water, but this is really showing strong warming or cooling trends where the water temp is changing fast. This probably makes the bass move and harder to catch.

One other thing I see. While the catch rate may be not as good, people are still catching bass when the conditions are bad. So there really is no bad time to bass fish, only better times

Something to think about.....
Jim

[Travis C.]

Great info Jim. Stable temps are a good thing. We get used to it just like the fish do...example we still function better the 10 day than day 1 of 35 degrees.

This is how I factor in the water temp when it is not directly related to the spawn. Any lake can either fish "big" or "small" and that is not relative to the actual size of the water shed. Bass are cold blooded and the water plays a major factor with the mood of the fish.

A lake that fishes "big" means water is usually comfortable enough to the fish and they are out foraging in broad areas for food. Like post spawn fish in high 60's or better water. They are easy to catch and you can catch them everywhere.

A lake that would fish "small" is the opposite. The window of where and how much that fish is willing to go for food diminishes greatly. That is usually winter but not always the case as you have to drop it on the fishes noses for it to bite.

Given strong spring fronts it can go from one to the other as well. Knowing how fish relate to water temp changes will help you pick that up and give you a better idea of what tactics to use before hitting the water.

Kind of a summary statement, it means more less the window of to what extent a fish will to go get food.

That is why I still search with a crankbait all year long. You either need to crawl it or speed it up or be more precise with your casts depending on the mood of the fish.

[Jim]

Thanks for the insight Travis,

While I can develop some cool maps and models of fish distribution and habitat that point to high probability locations, you still have to be a good fisherman to catch them. Clearly, you know how to catch them.

I notice this with the sidescan. Sometimes I am on a pile of fish, but I can't get them to bite. Finding them is the first problem and the getting them to bite is the next one.

I am sure that you and many others on here are way better fishermen than I am. But that is the fun thing about fishing, there is always more to learn.