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| Do muskies actually consume more fish before ice up and that's why they are so fat( besides eggs in females). Or is it due to slower metabolism with lower water temps? | |
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| in my unscientific opinion, a lot of the fat fall muskies we catch are fat all year long but live most of the season in places where they don't run into anglers or baits very often. i never bought the theory that skinny or normal girthed muskies suddenly start eating all the time in the fall and that's why they put on weight. lots of the fattest fish we catch in the fall are also some of the cleanest fish of the year. obviously they feed heavier in the fall but a fish putting on a bunch of weight in the span of 4-6 weeks with cooling water temps just doesn't make that much sense. | |
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Location: Ashland WI | I had actually thought they fed more in the summer when their metabolism was faster. | |
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| Do males put on girth as well? | |
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Location: Ashland WI | Sudszee - 11/13/2017 4:09 PM
Do males put on girth as well?
I'll leave this one for todd..... | |
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Location: Green Bay, WI | I think they probably feed whenever they can, but they clearly capitalize on the spawning behavior(s) of the prey species they feed on--like Shad, Ciscoes (Lake Herring) and Whitefish. If those fish are congregated to spawn, experience has shown us that the muskies aren't far away. So yes, I do think they tend to feed a lot in the fall as winter approaches because, well, they can.
That said, I think they gain more weight in the fall because they're eating high-calorie prey at a time when their own metabolism has slowed. Simply put, they're eating more than they're using so they gain weight. And that's not a bad thing given that they need to devote (caloric) energy into gamete production. But again, since they're poikilothermic and their body temperature is within a degree or so of the water they're swimming in, their metabolism can't help but slow.
So essentially they're sitting on the couch in a cold room, watching television, eating little smokies and potato chips and not working out. You'd get fat too!
TB | |
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Location: Chisholm, MN | If they bite more in the fall, why are they so freaking hard to catch? | |
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Location: Eastern Ontario | Give me Sept 12 months of the year and I'm a happy man. In Nov and Dec its a lot of of fruitless hours hoping we encounter a monster that has spent the summer out in Lake Ontario feeding on Lake Trout and other deep water forage. Or as I call it fishing for Unicorns | |
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Location: Green Bay, WI | Kirby Budrow - 11/14/2017 3:51 PM
If they bite more in the fall, why are they so freaking hard to catch?
I didn't say they bit more in the fall, only that they *ate* more... | |
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| Egg mass is a factor. Slow metabolism is a factor. Also much of their food is also fatter and full of eggs in the fall, so they're getting a lot more out of a meal. They have to eat more often in warmer temperatures, but they are likely exerting a lot more effort to eat food that's not as substantial. | |
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Location: Grand Rapids, MI | Without going and digging up past articles,etc. (meaning I'm not going to cite a source other than memory). I believe that most of the super fish harvested in October, November, December have relatively empty stomachs and lots of eggs. That leads me to believe that any actual "fat" is accumulated in late August and September as water temps drop. It appears very little feeding is happening late in the year. | |
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Location: oswego, il | Based on most of the late fall and winter fish that crap all over my boat, i think they either do eat alot or digestion slows down more than what they have ate making them like most musky fisherman full of #*#*.
Males put on girth during the spawn if you know what i mean. 
Edited by ToddM 11/16/2017 2:09 PM
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| Will Schultz - 11/16/2017 1:21 PM
Without going and digging up past articles,etc. (meaning I'm not going to cite a source other than memory). I believe that most of the super fish harvested in October, November, December have relatively empty stomachs and lots of eggs. That leads me to believe that any actual "fat" is accumulated in late August and September as water temps drop. It appears very little feeding is happening late in the year.
I don't necessarily disagree with you, Will. But catching a fish with little or nothing in its belly might just be an indication that those fish were hungry and attempting to feed when caught. | |
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Location: Already Gone | esoxaddict - 11/16/2017 2:14 PM
Will Schultz - 11/16/2017 1:21 PM
Without going and digging up past articles,etc. (meaning I'm not going to cite a source other than memory). I believe that most of the super fish harvested in October, November, December have relatively empty stomachs and lots of eggs. That leads me to believe that any actual "fat" is accumulated in late August and September as water temps drop. It appears very little feeding is happening late in the year.
I don't necessarily disagree with you, Will. But catching a fish with little or nothing in its belly might just be an indication that those fish were hungry and attempting to feed when caught.
Yes. I have to agree with Jeff. The ones that I am lucky to boat in mid to later November were feeding on spawning ciscoes. I know this, because I was puposely live bait fishing for them...with ciscoes. In popular spawning areas. Along with Bondy baits, imitating spawning/struggling ciscoes. Along with several other guys, doing the same. It's kind of a known tactic, and if you can stand the weather, it's semi-productive if done right.
I have to assume that they were hungry. What else would they be doing attacking my bait presentation.? | |
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Location: Green Bay, WI | Will Schultz - 11/16/2017 1:21 PM
Without going and digging up past articles,etc. (meaning I'm not going to cite a source other than memory). I believe that most of the super fish harvested in October, November, December have relatively empty stomachs and lots of eggs. That leads me to believe that any actual "fat" is accumulated in late August and September as water temps drop. It appears very little feeding is happening late in the year.
Most of the big fish I've caught in Green Bay in October/November are crapping all over the place in the boat, lol. So that certainly means they've been feeding--hard to have fish poop on an empty stomach. That being said, if their metabolism is slower due to cooler water temperatures, it must not be *that* much slower if there's no food in their stomach. I've never seen anything in the literature that quantifies the degree to which their metabolism slows, but I would have to think that it doesn't slow all that much if 1) they're pooping all over the boat, with 2) an empty stomach.
So I think they are basically converting forage into biomass just as quickly in the fall as they are in the summer, for the most part. But in the warmer water of summer it takes more of those calories just to keep the lights on...and therefore they don't put on the weight during those months. | |
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Location: Already Gone | tcbetka - 11/16/2017 6:16 PM
Will Schultz - 11/16/2017 1:21 PM
Without going and digging up past articles,etc. (meaning I'm not going to cite a source other than memory). I believe that most of the super fish harvested in October, November, December have relatively empty stomachs and lots of eggs. That leads me to believe that any actual "fat" is accumulated in late August and September as water temps drop. It appears very little feeding is happening late in the year.
Most of the big fish I've caught in Green Bay in October/November are crapping all over the place in the boat, lol. So that certainly means they've been feeding--hard to have fish poop on an empty stomach. That being said, if their metabolism is slower due to cooler water temperatures, it must not be *that* much slower if there's no food in their stomach. I've never seen anything in the literature that quantifies the degree to which their metabolism slows, but I would have to think that it doesn't slow all that much if 1 ) they're pooping all over the boat, with 2 ) an empty stomach.
So I think they are basically converting forage into biomass just as quickly in the fall as they are in the summer, for the most part. But in the warmer water of summer it takes more of those calories just to keep the lights on...and therefore they don't put on the weight during those months.
I like this explanation. it's an interesting discussion.
I also want to say that I enjoy your posts Tom...I for one, am glad to see you back on here again.
Thanks.
Mark | |
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Location: Green Bay, WI | Mark Hoerich - 11/17/2017 8:43 AM
I like this explanation. it's an interesting discussion.
I also want to say that I enjoy your posts Tom...I for one, am glad to see you back on here again.
Thanks.
Mark
You're welcome Mark--and thanks for the comment! It's nice to be back on the board again, now that my "home remodeling & construction" season is finally coming to an end. There's only so much of that a guy can take, and I reached my limit well over a month ago...
TB | |
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| I catch them on Suckers in late OCT all the way to freeze up--usually mid Nov here in N.WI..... They sure like those 16-18" live suckers in the fall---- And many times they swallow them almost instantly-- So I know they are feeding...... And I fish the same lakes throughout the season----- I definitely catch Fatter and Heavier fish from say Mid-Sept to Ice up than any other time of the season...And My Biggest Fattest fish always come very late in the season......If someone thinks they don't feed heavily in the Fall then that person has never done much musky fishing THROUGHOUT a whole fishing season....I also agree that while they may slow down some as the temp falls.. I don't think its that much.....Many Still Fight Like Hell in the cold water | |
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Location: Green Bay, WI | Throughout the animal kingdom there are examples of creatures feeding vigorously with the approach of winter, in order to increase their fat stores as a means of survival. Bears, squirrels, bats, hedgehogs, and (according to Google) any number of other creatures. Heck, even my two dogs want to eat more in the fall as winter approaches. Therefore it seems quite reasonable to assume that fish are doing the same. And it shouldn't take much to do, given (as mentioned above) decreasing water temperatures result in a slower metabolism by default.
My only other point was that if a musky is crapping all over your boat when caught, then they have food in their GI tract. So they must be feeding in order to put food into said GI tract, because there is no other way to get food into the lower GI tract. And if taxidermists are reporting empty stomachs in fish caught in the fall (and then submitted for taxidermy), then it's not too much of a stretch to infer that the fish's GI tract is working at a pretty good rate...even in the fall.
Colder water (decreased metabolism) plus schooled prey (less energy expended for a meal) equals fatter muskies, by my thinking. | |
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| So, it sounds like stomach acid does its thing and metabolism slows at lower temps causing fat stores. Makes sense. I'm not convinced the eat more though. You would think they would be easier to catch and more would be caught. | |
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Location: Green Bay, WI | Well I believe the thought is that, by focusing on schools of pre-spawn and spawning prey (Cisco, Whitefish, Shad, etc), their prey is simply more abundant--so they eat more calories, just for that reason alone. And from an evolutionary standpoint, this would seem to make sense. Life is about energy management, and the more energy an organism can conserve...the better it usually does in the long run. I'm not talking about humans who have something of an "artificial" energy management system, but rather more along the lines of hunters & gatherers.
All living organisms need energy to survive. That energy comes from the metabolism of glucose, fats and protein, for the most part. Certainly it involves oxygen to a large degree (for aerobic metabolism anyway), but in aerobic organisms the fuel for ATP (ie; energy) production is basically glucose. Proteins in the diet are broken down into amino acids which can then be used by the organism as building blocks for their own muscle mass, but energy to drive the organism is largely from adenosine triphosphate. Since this is the fuel that drives the bus so to speak, pretty much all biological processes require it to continue.
So the thing to realize is that it takes energy to make energy. When a musky has to chase down food, that takes energy. Muscles need ATP to make the fish move. Their brain needs ATP to keep the lights on and drive their activities. Their red blood cells require ATP to bind oxygen, and their heart certainly needs ATP to circulate that blood to all parts of their body. In other words--it takes energy to go get energy. There's no way around it. Period. We use the concept of "calories" to describe it, but it all comes down to the production of ATP in the cells that require it to power them.
So the take-home point is that if a musky has to chase down a single 5-6" shad and burns more calories doing so than it gains from ingesting that single shad...it's running on an energy deficit. That's not the way to maintain life. So it should come as no surprise that the fish have learned (through evolution for the most part) that when cisco and whitefish school to spawn in the fall, it takes less energy to get a meal than it does to chase them down one by one. I doubt the fish think it through like that, but it's the end result nonetheless. Why spend 100 calories getting 200 from a single shad, when you can spend 200 to get 2000 calories eating 10 shad from the same bait ball? That sort of thing. In the first case you only double your energy spent, but in the latter instance you recover ten-fold your investment.
Sorry for the long answer, but I needed a more lengthy response to explain why (physiologically) I think we see these fish doing what they seem to be doing in the fall.
EDIT: I forgot to mention Sudszee, that I don't believe the rate of the enzymatic reaction(s) in the musky's GI tract decreases much as the water temperature drops. As with all enzymatic reactions that I know of, an increase of about 10 degrees Centigrade (10C) will virtually double the rate of the reaction catalyzed by those enzymes. Certainly different enzymes have different temperature-dependent coefficients, but we can use 10C as an example as it equates to an easy-to-remember 50F. So if it gets 10C cooler, then the rate of the reaction(s) will be roughly halved. But the thing is that 10C (50F) is a BIG drop in water temperature--so in all likelihood we're not talking about gastric enzyme-induced reactions that are actually halved in terms of rate. This is supported by the observations that we've already been talking about: The observations that 1) many fish crap all over the boat when they're feeding a lot, 2) many fish caught in the fall crap all over my boat (thanks PointerPride), and 3) taxidermists apparently often report that large fish caught in the fall are found to have an empty stomach.
So this tells me that while the fish's overall metabolism is likely diminished in the fall due to falling water temperatures, the rate of digestion likely isn't.
Edited by tcbetka 11/22/2017 5:22 PM
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| If I remember correctly the biological explanation lies with the shift in metabolism, slowing as the water cools. They don't eat more but move less. Maybe this explains the short fall feeding windows. | |
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Location: Green Bay, WI | I'm really not sure how much of a drop they have in metabolism, to be honest. Like I mentioned above--the biological reactions in metabolism (Citrus Acid Cycle, for example) are all mediated by enzymatic activity. And when you consider that it likely takes an 8-10C (46-50F) degree drop to halve the activity of most of these enzymes, then how much a decrease in "metabolism" is there really?
If summer water temperatures are in the 70-80F range, for the sake of discussion, and then the water freezes at 32F, that's a difference of about 40-50F. But the water temperatures in the fall are typically in the 40-45 degree range when the Ciscoes are spawning--and almost 50F when Whitefish spawn. Therefore compared to the summer water temps when we consider the fish's metabolism to be highest, we're talking about a drop of about 30-40F. Thus it doesn't seem as though the fish's metabolic rate is slowed as much as we might think--and again, the fish are still crapping all over the place when you handle them...so certainly their gut metabolism seems to be working pretty well.
Edited by tcbetka 12/3/2017 12:20 PM
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| While it is known that temperatures effect enzymatic activity of many enzymes in a gaussian dependence, I agree that direct manipulation of enzymatic turnover due to temperature is unlikely. This metabolic shift does occur during acclimation to cold temperatures and causes major changes in phosphorylation state of many mitochondrial enzymes. This is specifically true in the liver, gills and brain. You can also imagine that the membrane composition would be altered to maintain the fluid mosaic needed for oxphox and even the citric acid cycle due to increased protein density seen in mitochondria in fish exposed to cold temperatures.
I haven't seen any data that argues against a change in eating habits in response to temperature acclimation as it is indicated in multiple studies (will come back and add citations can't remember off hand), where there is an increase in pentose phosphate pathway in response to an increased need for fatty acids, perhaps for gametogenesis.
I would suspect after more reading that there must be some truth tcbetka to a shift to increased consumption during acclimation to cold temperatures. After reading it seems likely that this increase "appetite" would then return to baseline after sustained cold temperatures.
This is an interesting subject and I will devote more time to reading papers about this. | |
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Location: Grand Rapids, MI | esoxaddict - 11/16/2017 3:14 PM
Will Schultz - 11/16/2017 1:21 PM
Without going and digging up past articles,etc. (meaning I'm not going to cite a source other than memory). I believe that most of the super fish harvested in October, November, December have relatively empty stomachs and lots of eggs. That leads me to believe that any actual "fat" is accumulated in late August and September as water temps drop. It appears very little feeding is happening late in the year.
I don't necessarily disagree with you, Will. But catching a fish with little or nothing in its belly might just be an indication that those fish were hungry and attempting to feed when caught.
The original post was asking why they're so fat. I was attempting to explain that it's eggs and not fat or a belly full of fish that is making them heavy. | |
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| I've never seen a fish pictured in late fall that doesn't appear to be larger (fatter) than let's say, summer. All of them can't be females pictured. | |
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Location: Grand Rapids, MI | This relates to pond fish (koi) but should still be applicable because cold blooded is cold blooded
In warmer water (60-85 degrees) the metabolism of the fish is high and they can be fed 2-4 times per day. At this time you should be feeding a food with a high protein level such as Pond Care Summer Staple Food. If the water rises to 90 degrees or above you should stop feeding. In spring and fall when your water temperatures fall to 50-60 degrees, you should reduce feeding to once every 1-2 days and feed a low protein food such as Pond Care Spring and Autumn food. When the temperatures drop to below 50 degrees stop feeding the fish. On warm days the fish may become active and "beg" for food. Don't be fooled. Stay strong and do not feed. If the fish do need a little food, they will find enough growing in the pond. The algae that coats the pond liner is all they need. These cold temperatures slow the metabolism of your fish and food will not be properly digested. It can take 3-4 days for the fish to digest the food. It's not worth the fish's life to give it food.
http://www.watergarden.org/Pond-Info/Fish-Care-Feeding
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Location: Grand Rapids, MI | Sudszee - 12/7/2017 1:10 PM
I've never seen a fish pictured in late fall that doesn't appear to be larger (fatter) than let's say, summer. All of them can't be females pictured.
They're all going to be heavier if they only need to eat once every three days versus three times each day but the really fat appearing fish will all be females. Generally speaking most over 42" are females (though exceptions exist in certain locations/strains). | |
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Location: Green Bay, WI | bbeaupre - 12/6/2017 4:12 PM
SNIP...
I haven't seen any data that argues against a change in eating habits in response to temperature acclimation as it is indicated in multiple studies (will come back and add citations can't remember off hand), where there is an increase in pentose phosphate pathway in response to an increased need for fatty acids, perhaps for gametogenesis.
I'm not sure that I follow what you're saying in that paragraph. Are you saying that *are* changes in eating habits when the water temperature changes and the fish acclimate accordingly?
I would suspect after more reading that there must be some truth tcbetka to a shift to increased consumption during acclimation to cold temperatures. After reading it seems likely that this increase "appetite" would then return to baseline after sustained cold temperatures.
This is an interesting subject and I will devote more time to reading papers about this.
I think there is as well. I think muskies, like most other predators, are likely opportunists to some degree. And over eons of time, they've just gotten conditioned to taking advantage of what nature gives them. So if there is a substantial tulibee spawn going into the winter, then the fish will take advantage of that.
Isn't it interesting how nature works--muskies (and other spring-spawning predatory fish) need to take in calories in the fall for gamete development, and nature obliges by giving them prey that schools when spawning. Awesome stuff!
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| tcbetka - 12/7/2017 6:17 PM
bbeaupre - 12/6/2017 4:12 PM
SNIP...
I haven't seen any data that argues against a change in eating habits in response to temperature acclimation as it is indicated in multiple studies (will come back and add citations can't remember off hand), where there is an increase in pentose phosphate pathway in response to an increased need for fatty acids, perhaps for gametogenesis.
I'm not sure that I follow what you're saying in that paragraph. Are you saying that *are* changes in eating habits when the water temperature changes and the fish acclimate accordingly?
I haven't seen any studies that say definitively that eating habits do NOT change. There are multiple that suggest they do during the acclimation stage, but do not suggest mechanism.
There are multiple studies that confirm significant metabolic changes that occur during during acclimation to lower temperatures. It seems that it is still largely unknown how this impacts homeostasis of the fish, but my hypothesis is that this change may funnel more resources into pathways (largely hepatic ) that lead to storage (fat ) perhaps by blunting the TCA cycle or directly preventing conversion of Glyc-3-P to pyruvate. Another possibility would be to force acetyl coA toward the lipid pathway away from TCA cycle and conversion to citrate.
It seems that this could be done directly at the enzyme targets of both pathways or indirectly by blunting the TCA cycle. This is interesting because the result of decreased flux through the TCA cycle which results in lower levels of NADH, GTP and other reducing equivalents ultimately leading to a decrease in available ATP.
Sorry for long winded answer, hope this is more clear on my thoughts.
Edited by bbeaupre 12/8/2017 12:19 PM
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Location: Grand Rapids, MI | tcbetka - 11/22/2017 12:32 PM
So this tells me that while the fish's overall metabolism is likely diminished in the fall due to falling water temperatures, the rate of digestion likely isn't.
Could they be crapping all over your boat because the rate of digestion had slowed so much that they're eating beyond their digestive rate? Late fall muskie poop is very different from summer muskie poop and appears to be less digested (more scales, bones, etc). | |
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Location: Green Bay, WI | I suppose it's possible, but generally speaking the gastrocolic reflex dictates...in with the new, out with the old. So that means that if there's food in the stomach, there's poop in the bowel--and it's heading for the great outdoors. That said, the fish aren't always pooping *voluntarily* mind you. Some of it is pressure from angling and some of it is certainly from their autonomic nervous system stimulus, related to the catch.
The other thing is that I really don't know how any animal is going to out-eat their rate of digestion. They would be satiated to the point of not wanting to eat any longer, simply because (I'd think) they wouldn't be able to physically get any more food into their stomach. Then again my dog seems to ALWAYS want to eat, even when she's just eaten. But I think that's more of a psychological thing--as you saw that night we were eating pizza while watching the football game.
So I tend to think that although the fish may indeed have a somewhat slowed rate of metabolism, it isn't nearly as significant as we might think. Don't forget that we anglers tend to think of warm water temperatures in the summer because the surface temperatures exceed 70 degrees. But in all reality the fish are going to seek out water temperatures most desirable to them...which means finding deeper/cooler water. Therefore the temperature drop between summer and fall months, in terms of its significance on their metabolic rate, really doesn't seem as significant as we like to make it out to be.
At least that's my thinking anyway. | |
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Location: Hayward, Wisconsin | tcbetka wrote: "Don't forget that we anglers tend to think of warm water temperatures in the summer because the surface temperatures exceed 70 degrees. But in all reality the fish are going to seek out water temperatures most desirable to them...which means finding deeper/cooler water. Therefore the temperature drop between summer and fall months, in terms of its significance on their metabolic rate, really doesn't seem as significant as we like to make it out to be."
LR: Tom, based on my observations while radio tracking muskies in Ontario's Eagle Lake, I particularly disagree with ..."finding deeper/cooler water.", when it comes to digestion. On the contrary, the big muskies (mostly females, but not all) did their feeding in the deeper, cooler (by an average of around 10 degrees F) and then on the average of every third day in mid summer (July) moved as much a several miles to the warmest water available in a fairly shallow bay! My hypothesis, based on these observations was that they were in the warmer water to warm up and speed up digestion. Obviously I couldn't "ask" them when we did recapture them, so I guess we'll never know for sure, but it did make sense to me and Dr. Lebeau and many other seasoned muskie anglers that I have discussed it with. | |
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| Hi Larry, off topic but does any of your data show reduced travel in late fall and into ice times? | |
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| But in all reality the fish are going to seek out water temperatures most desirable to them...which means finding deeper/cooler water.
Yes, and no. Muskies do clearly seek preferred water temps, it's just not deeper/cooler.
The 2011 Melton Hill study using radio telemetry and internal temperature sensors showed that muskies prefer 68-77 degree water when oxygen and forage is available in both cooler and warmer water than that. If only cooler water is available, they congregate in the warmest possible water.
https://www.coopunits.org/Tennessee/Research/Completed/3.8626377729E...
To me, this suggests that if they're moving to an area of cooler water when the preferred warmer water is available, it's because the warmer water doesn't offer something they need (food, oxygen, ???). For example, if they're hungry and the available forage prefers cool water the need to eat will drive them until they're satisfied - but they're not going to stay/live there.
The phenomenon of muskies moving out to deep/cool areas to feed and then up to shallow/warm areas when not feeding is well-observed. Anyone who's cursed the sunbathers on a Minnesota reef or sand flat knows this. But is the shallow move to speed digestion, or just because it feels good to them? Or more likely it does both...increased metabolism and feels nice? I just know that the shallow-structure fish near deep-water forage behave differently than shallow-water fish near shallow-water forage, and this has meaning when trying to catch them.
My personal non-biologist hypothesis is just common sense: they're fat in the fall because they're eating more. Why are they eating more? Because they can...it's easier to feed because the forage is more concentrated in vulnerable near-shore areas. Summer fish with the same easy food access get stupid fat too.
Edited by Glaucus_ 12/11/2017 9:06 AM
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Location: Green Bay, WI | I would agree about them eating more forage because that forage is more available. I think they've learned this over many many years of experience, essentially now to the point it has become "instinct" to them. Shouldn't be surprising I guess. My point about them finding cooler water was meant as a further illustration as to how little change in temperature their two extremes might actually be. Since water freezes at 32F and is slightly warmer at the bottom of the water column, then it's not going to be any colder than that. And if they prefer water temperatures around 70F, then the most we're talking about is a 38F temperature range--which may not be all that much when it comes to the activity of their digestive enzymes.
So in terms of why they put on weight in the fall, I still hypothesize that it's because they're 1) eating more forage because it's more readily available, 2) they don't have to do as much work to go get that forage given point #1, and 3) their metabolism has slowed a bit in the cooler water. Whether or not their metabolic rate has slowed significantly might be debatable given what's been discussed thus far (ie; digestive enzyme activity), so maybe it's as simple as them eating more without having to spend as many calories to go get it.
Maybe it really is like us sitting on the couch watching TV, and pigging-out on junk food? | |
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Location: Green Bay, WI | Larry Ramsell - 12/11/2017 7:38 AM
LR: Tom, based on my observations while radio tracking muskies in Ontario's Eagle Lake, I particularly disagree with ..."finding deeper/cooler water.", when it comes to digestion. On the contrary, the big muskies (mostly females, but not all) did their feeding in the deeper, cooler (by an average of around 10 degrees F) and then on the average of every third day in mid summer (July) moved as much a several miles to the warmest water available in a fairly shallow bay! My hypothesis, based on these observations was that they were in the warmer water to warm up and speed up digestion. Obviously I couldn't "ask" them when we did recapture them, so I guess we'll never know for sure, but it did make sense to me and Dr. Lebeau and many other seasoned muskie anglers that I have discussed it with.
Yes, I recall those points in the article you wrote. Do you happen to remember the water temperatures that you found in those different places? I'll have to pull out the article(s) and review them this week, because it's been some time since I read through them.
I'll bet their migration into warmer water was instinctive, given the point you made about digestion. I doubt they put much thought into it, LOL. | |
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Location: Green Bay, WI | Sudszee - 12/11/2017 8:19 AM
Hi Larry, off topic but does any of your data show reduced travel in late fall and into ice times?
On a related topic to the study that Larry did on Eagle Lake, there is on-going research in the bay of Green Bay right now, on the migration patterns of (angled) radio-tagged muskies. I haven't heard any sort of preliminary results just yet as it just started this year to my knowledge. But there are apparently several listening stations throughout the bay (including up north) that will record any migratory movement from the fish that have been radio-tagged. I don't have a map of the receiver sites, but to my knowledge they are located by the main rivers going into the bay, as well as across the bay up near the Marinette area. Since the data is gathered from these sites periodically, it should give a temporal migration pattern. Then we'll have some idea of the answer to your question...at least for the fish sampled (tagged) in the bay of Green Bay. | |
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| Makes me think the fish we catch in shallow water have been hanging out there for a few days and are about to head back out into deeper water to feed again. The question then is do they feed in deeper cooler water because they prefer that, or do they just instinctively know that's where the food is?
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| In the Melton Hill study, when forage was available in areas of preferred water temp (68-77) the muskies stayed put. When the food isn't there? Well, species that can't find food get extinct pretty fast.
And being hungry isn't the only reason a muskie hits a lure. It might have just moved in after feeding and it "eats" again because of reaction or claiming territory or just plain meanness and then it's stuck on a hook.
Edited by Glaucus_ 12/11/2017 1:25 PM
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Location: Hayward, Wisconsin | Glaucus: My tracking work ended in mid September, so I can't personally answer your question. Some tracking studies I have read had the big females moving shallow...UNDER THE ICE (as shallow as 3 feet of water) in or near the spawning grounds.
Tom: Without digging my data out, I believe the deep feeding areas in the main lake basin were around 62 degrees or so and the shallow about 10 degrees warmer. | |
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Location: Grand Rapids, MI | tcbetka - 12/11/2017 10:40 AM
So in terms of why they put on weight in the fall, I still hypothesize that it's because they're 1) eating more forage because it's more readily available, 2) they don't have to do as much work to go get that forage given point #1, and 3) their metabolism has slowed a bit in the cooler water. Whether or not their metabolic rate has slowed significantly might be debatable given what's been discussed thus far (ie; digestive enzyme activity), so maybe it's as simple as them eating more without having to spend as many calories to go get it.
You forgot the most important reason. Eggs!! What they eat comes and goes, 6+ pounds of eggs stays put. | |
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| You forgot the most important reason. Eggs!! What they eat comes and goes, 6+ pounds of eggs stays put.
Look at all of the egg mass present in this 38" muskie from October that died during Sean Landsman's study...now imagine what it's like for a mature 50" fish that's much more productive.
Those eggs are carried up pretty high inside the body, so maybe aren't themselves what makes a fish look fat? But they sure push everything else down and out, so anything they eat is bulging.
http://projectnoblebeast.blogspot.com/2009/10/necropsy-notes-genera...
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| That would explain the additional mass on a female.
Maybe part of it is the caloric content of their diet. Half the food chain comes with a side of eggs in the fall, so basically everything that eats is getting more calories out of a meal. | |
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Location: Green Bay, WI | Will Schultz - 12/12/2017 9:36 AM
tcbetka - 12/11/2017 10:40 AM
So in terms of why they put on weight in the fall, I still hypothesize that it's because they're 1) eating more forage because it's more readily available, 2) they don't have to do as much work to go get that forage given point #1, and 3) their metabolism has slowed a bit in the cooler water. Whether or not their metabolic rate has slowed significantly might be debatable given what's been discussed thus far (ie; digestive enzyme activity), so maybe it's as simple as them eating more without having to spend as many calories to go get it.
You forgot the most important reason. Eggs!! What they eat comes and goes, 6+ pounds of eggs stays put.
Well certainly they develop gametes over the winter...but I'm talking about in fall, when the food bag is on. Also, those eggs have to be made from something--I mean, it takes calories to create gametes. Either they convert caloric intake to fat or gametes, but they need more calories either way. How much egg mass can an anorexic musky create after all? | |
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Location: Green Bay, WI | Glaucus_ - 12/12/2017 10:57 AM
Look at all of the egg mass present in this 38" muskie from October that died during Sean Landsman's study...now imagine what it's like for a mature 50" fish that's much more productive.
Those eggs are carried up pretty high inside the body, so maybe aren't themselves what makes a fish look fat? But they sure push everything else down and out, so anything they eat is bulging.
http://projectnoblebeast.blogspot.com/2009/10/necropsy-notes-genera...
Very interesting image.
I believe I've read a paper (LeBeau's thesis maybe?) that discussed how the eggs change over the course of the months leading up to the spawn. I believe I remember that the eggs become larger as they ripen, but I read through most of that thesis about 8-9 years ago...if that's where it even was I read this. I believe that it was yolk enlargement responsible for the increase in egg size (mass) as they ripened leading up to the spawn.
Larry, do you remember seeing this information in Dr. LeBeau's doctoral work? | |
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| It all-but goes without saying that the eggs will change and grow between initial development and the spawn. The point is simply that they are present in large numbers already in October, and this undoubtedly is one part of the "fat (female) fish" equation.
In the blog link above, Landsman explains in more detail about the fish shown:
"...took a small portion of the ovaries and counted the number of eggs then extrapolated the total number of eggs using the length of the ovary. There were 606 eggs in a 29 mm/1.1 in segment of one of the ovaries. The total length of the removed ovary was 43.5 cm/17.1 in. I will forego reporting all the calculations, but there were an estimated 18,180 eggs (give or take) in this 38 in female. Scott and Crossman (1983) reported a range of 6,000 to 265,000 eggs in adult muskellunge."
So, a relatively young 38" female had a 17" ovary containing ~18,000 eggs.
Now imagine a mature 50" female with ~200,000 eggs...
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Location: Grand Rapids, MI | tcbetka - 12/12/2017 1:10 PM
Will Schultz - 12/12/2017 9:36 AM
tcbetka - 12/11/2017 10:40 AM
So in terms of why they put on weight in the fall, I still hypothesize that it's because they're 1) eating more forage because it's more readily available, 2) they don't have to do as much work to go get that forage given point #1, and 3) their metabolism has slowed a bit in the cooler water. Whether or not their metabolic rate has slowed significantly might be debatable given what's been discussed thus far (ie; digestive enzyme activity), so maybe it's as simple as them eating more without having to spend as many calories to go get it.
You forgot the most important reason. Eggs!! What they eat comes and goes, 6+ pounds of eggs stays put.
Well certainly they develop gametes over the winter...but I'm talking about in fall, when the food bag is on. Also, those eggs have to be made from something--I mean, it takes calories to create gametes. Either they convert caloric intake to fat or gametes, but they need more calories either way. How much egg mass can an anorexic musky create after all?
Eggs start developing in mid/late-August in most areas, by September they're significant and by October 10+% of weight could be eggs. If I recall correctly our modern day record (mid-October fish) had 8# of eggs, that is 14%. So, I'm back to saying that most of any actual "fat" in a fish is accumulated in August and early-September because after that egg growth has to be using up most of the caloric intake. | |
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| Do you think they're effectively "programmed" to consume more food during egg development? Certainly would explain why the best fishing starts in late august on some of our favorite waters. | |
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Location: Hayward, Wisconsin | Tom: I believe you are correct about Dr. Lebeau's thesis containing the information you espoused.
Glaucus: 200,000 eggs is miniscule compared to the O'Brien muskie from the Moon River in 1988. According to Dr. Ed Crossman, Dr. Lebeau did an egg count of the ovaries from that fish and found around 850,000 eggs!! Talk about egg bloat.
Also note that yes, eggs do grow until ripe, different waterbodies and different strains of muskies produce different SIZED eggs! This was noted by both noted WDNR Researcher Leon Johnson and WDNR's Art Oehmcke, who was in charge of the Woodruff hatchery during the mid 1900's.
Will: While I agree that 10% of body weight could be eggs in the fall, according to Dr. Lebeau, it could be as much as 20% by the time they are ready to spawn! As for the Modern Day record, it only contained 2 1/3 pounds of eggs (I personally weighed them). It is likely that that fish was at the end of its life or had ceased viable spawning. Also, it contained very little body fat.
EA: good question, but flies in the face of the belief that they eat more in the summer than in the fall due to metabolism. Something we may never know for sure. | |
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Location: Grand Rapids, MI | Larry Ramsell - 12/13/2017 7:00 AM
Will: While I agree that 10% of body weight could be eggs in the fall, according to Dr. Lebeau, it could be as much as 20% by the time they are ready to spawn! As for the Modern Day record, it only contained 2 1/3 pounds of eggs (I personally weighed them). It is likely that that fish was at the end of its life or had ceased viable spawning. Also, it contained very little body fat.
Thanks, LR!! | |
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| In September - October - early November on Chautauqua Lake they follow the perch schools. If the perch are at 50' or 12' that's pretty much where the musky are on the outskirts of these schools. I haven't caught nearly as many as some here, but my experiences show they do bite better in the fall. I know when we used to keep big pike a long time back, fish taken in late_Oct-Nov were definitely filling up with eggs, so I suspect the same is true of musky's. | |
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Location: Tampa, Florida | NPike - 12/13/2017 6:27 PM
In September - October - early November on Chautauqua Lake they follow the perch schools. If the perch are at 50' or 12' that's pretty much where the musky are on the outskirts of these schools. I haven't caught nearly as many as some here, but my experiences show they do bite better in the fall. I know when we used to keep big pike a long time back, fish taken in late_Oct-Nov were definitely filling up with eggs, so I suspect the same is true of musky's.
Hmm, interesting.  | |
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Location: Michigan | NPike - 12/13/2017 7:27 PM
I haven't caught nearly as many as some here, but my experiences show they do bite better in the fall.
Are they biting better/more often or are they just all congregated in the same general area which makes them more susceptible to being caught by anglers who know they are there? | |
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| I don't believe they necessarily congregate any more in late fall than at other times of year. In the lakes I "normally" fish, I can generally "using the term loosely" find spots regardless of time of year. | |
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Location: Elroy, Wisconsin | Acids that break down proteins react at rate that is temperature dependent. The higher the ambient temperature the faster acids change sugars, carbohydrates and proteins into simpler compounds. Therefore, Muskies can and do digest proteins faster in warmer water (given adequate Oxygen levels) and they are found there in response to simple biochemical reactions. Then again, maybe they just feel better in warmer water and are happy there after feeding.
Mudpuppy | |
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| jasonvkop - 12/15/2017 11:24 AM
NPike - 12/13/2017 7:27 PM
I haven't caught nearly as many as some here, but my experiences show they do bite better in the fall.
Are they biting better/more often or are they just all congregated in the same general area which makes them more susceptible to being caught by anglers who know they are there?
Maybe there are just a lot fewer anglers in the fall, and the few that are out there catch all the fish... | |
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Location: Green Bay, WI | Mudpuppy - 12/17/2017 7:59 PM
Acids that break down proteins react at rate that is temperature dependent. The higher the ambient temperature the faster acids change sugars, carbohydrates and proteins into simpler compounds. Therefore, Muskies can and do digest proteins faster in warmer water (given adequate Oxygen levels) and they are found there in response to simple biochemical reactions. Then again, maybe they just feel better in warmer water and are happy there after feeding.
Mudpuppy
Exactly, but you're talking about a qualitative assessment, and I was attempting to hypothesize a quantitative one. I'm confident that their GI (digestive) rate is slowed somewhat in the colder water--but by how much? If the water temperature they prefer is 68-70F, and water freezes at 32F, then it can't have dropped more than about 36-38F...right? And this is even less when you consider that we normally fish waters that are no colder than about 38-40F here in Green Bay in the fall. So this means about a 30F temperature drop, compared to their "preferred" water temperatures. Therefore, is the enzymatic activity in their gut halved? I seriously doubt it. Rather I think it's probably down 30-40% at most, which certainly doesn't seem to hurt their GI abilities.
Again, I've caught a number of fall muskies on Green Bay, and invariably they seem to crap all over the boat. So that means their GI tracts have made waste products, and by us handling them...they poop. All over the place. By definition, this could not happen if they hadn't digested their food. So they are certainly doing just that, I guarantee it. Which tells me that their GI activity is still going quite strong in the cooler waters of fall. | |
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| If the rate of digestion (breakdown of food items into usable compounds) slows down in cold water...does the rate of pass-through change as well? Or does peristalsis keep moving things along at the same pace and the food just doesn't get time to be as fully digested before it's kicked out? Someone mentioned earlier that there's a difference between summer poop and fall poop, and that's my experience too: summer seems to be more of a smooth paste, whereas the fall is more clumpy with more easily identifiable items such as scales.
Is it possible that a muskie is getting less food value in the fall due to less efficient digestion? This would lend support to a hypothesis/observation that they eat more, because they'd have to be ingesting more in order to get the same amount of energy if more is lost as waste, let alone to provide the additional energy needed to grow eggs.
I'm not a fish biologist, nor do I play one on TV. But I did stay at a Holiday Inn Express last night.
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Location: Green Bay, WI | Those are great thoughts actually. Especially the GI pass-through idea. I'll have to talk myself through it a bit...
Peristalsis shouldn't necessarily be slowed, but it may be. I mean, it's (largely) driven by the nervous system, which seems to work just fine in these fish even in cold water. Muskies have no problems whatsoever going after a 4-5 mph lure in 40F water, so certainly their motor neurons are firing just fine. I've seen that for myself, and you can also find ample video evidence of it on YouTube. So I'm going to go out on a limb and say that it's unlikely that muskies have a slowed digestive tract in cold temperatures solely due to decreased nervous stimuli of the gut.
With regards to the lumpy vs smooth feces thing, I can't say that I've seen all that much musky poop in the summer--so I can't say I've seen such a difference. That's not to say it doesn't exist...I've just never seen it. And maybe that's saying something right there, in that (as others have mentioned) they simply might have such a high GI transit time, that their gut is empty much of the time? However assuming that their fecal matter IS lumpy in the summer, I would suggest that it might be due to less well-digested portions of their prey. Maybe their GI system is working so fast in the summer that they're actually wasting calories through incomplete digestion? That's an interesting thought, but it might help explain why these fish gain more weight in the fall? So then,
1) Due to a slowed digestive process in the fall (through whatever mechanism), the digestive enzymes have a longer period of time to work on the prey eaten by the fish, resulting in more calories being absorbed...and thus more calories being made available to be converted into musky biomass.
2) Due to a (relatively) more rapid digestive process in the warmer/summer months, the digestive enzymes simply don't have as much time to work on the ingested prey, and thus digestion isn't as complete. Thus there are undigested "lumps" of prey remaining in the fecal matter of the musky.
Is this the case? I honestly don't know. And I don't know how you would ever really prove it, unless you had a musky in a large tank or a pond someplace (fish farm maybe?) and could study this sort of thing over a fairly long time (months to years). But it might well help explain some things in regards to the kinds of anecdotal observations we've been discussing in this thread.
TB | |
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| Could be a result of how their diet changes throughout the season. We know they eat a lot of ciscoes late in the fall on lakes where they are available. We know half those ciscoes are as full of eggs as they get. Eat different foods = your matabolism changes = so does your poop. Makes sense to me. | |
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1) Due to a slowed digestive process in the fall (through whatever mechanism), the digestive enzymes have a longer period of time to work on the prey eaten by the fish, resulting in more calories being absorbed...and thus more calories being made available to be converted into musky biomass.
2) Due to a (relatively) more rapid digestive process in the warmer/summer months, the digestive enzymes simply don't have as much time to work on the ingested prey, and thus digestion isn't as complete. Thus there are undigested "lumps" of prey remaining in the fecal matter of the musky.
While acknowledging that this is all just mental masturbation by a non-expert, I'll point out that you got my idea exactly backwards.
I was suggesting:
- same rate of peristalis year-round. (constant)
- a slower enzymatic process in the cold water period (independent variable)
- less efficient digestion in cold water period (dependent variable) resulting in more wasted food as observed by chunkier feces with more identifiable parts (ie., it pushed out before being completed digested)
- under this hypothesis a fish would need to eat more food in the fall to obtain the same amount of calories
- and there are obviously other variables at play, such as reduced need for calories when metabolism is slower due to the cold and increased need for calories to provide energy to the growth of reproductive cells, etc.
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Location: Green Bay, WI | Glaucus_ - 12/19/2017 3:52 PM
1) Due to a slowed digestive process in the fall (through whatever mechanism), the digestive enzymes have a longer period of time to work on the prey eaten by the fish, resulting in more calories being absorbed...and thus more calories being made available to be converted into musky biomass.
2) Due to a (relatively) more rapid digestive process in the warmer/summer months, the digestive enzymes simply don't have as much time to work on the ingested prey, and thus digestion isn't as complete. Thus there are undigested "lumps" of prey remaining in the fecal matter of the musky.
While acknowledging that this is all just mental masturbation by a non-expert, I'll point out that you got my idea exactly backwards.
I was suggesting:
- same rate of peristalis year-round. (constant )
- a slower enzymatic process in the cold water period (independent variable )
- less efficient digestion in cold water period (dependent variable ) resulting in more wasted food as observed by chunkier feces with more identifiable parts (ie., it pushed out before being completed digested )
- under this hypothesis a fish would need to eat more food in the fall to obtain the same amount of calories
- and there are obviously other variables at play, such as reduced need for calories when metabolism is slower due to the cold and increased need for calories to provide energy to the growth of reproductive cells, etc.
Yes, but their feces isn't as "chunky" in the fall, remember? It's more bird-crap-like: Pasty and sticks to everything. It's the summer feces that's chunkier, according to the reports in this thread. This would suggest to me that their digestive process might possibly be more efficient in the fall--due to prolonged period of digestive action. But I guess it depends upon the composition of the chunks I suppose. Since they are pretty much eating the same sorts of foods (proteins, fats and bones), without much "fiber" in their diets, the bulk-forming components of their diet wouldn't be as variable as you and I have. It's the changes in non-digestible fibers in our diet that (largely) tends to change the consistency of our stool. Eat more fiber, your gut tends to become more "regular" and your feces tends to be more solid and well-formed. Eat less fiber and your stools tend to be more irregular and softer in consistency. That said, there are other things that tend to cause our stools to be firmer for instance, like cheese...which constipates many people when eaten in significant quantities. Also, a rapid transit time like caused by conditions like irritable bowel syndrome or a viral infection would tend to cause soft stools and (ultimately) diarrhea.
Muskies obviously don't eat cheese--well maybe the ones in Green Bay might, but I'm betting not. But my point is that what they do eat is fairly consistent. Even though the species of prey might change throughout the year, it's still most likely to be some sort of fish species with protein, bone and a varying degree of fat content (the last of which can probably change stool consistency to some degree, I'd bet). Thus I think it's quite possible that the variations being seen/reported in stool consistency throughout the season might be more a function of transit time through the gut, and quite possibly also then as a function of degree of absorption of nutrients. I'm also betting that their digestive enzymes are able to break down bony tissue as well--although likely at a slower rate than soft tissues. Given that they have muscle tissue, they must have calcium ions--both for the action of their own muscles as well as for their own bone growth and development. That calcium has certainly to come from somewhere.
Finally, in humans a slow transit time through the gut usually means constipation, while a faster time usually means loose stools. But you're talking about an animal with over 15 feet of bowel--most of which is small bowel. Our large intestine is largely for the re-absorption of water...which will pretty much determine if your stool is softer or hard. Animals that are herbivorous (or partially so) tend to have a longer alimentary tract (gut) than carnivorous animals, and to my knowledge muskellunge would qualify as the latter. So I would expect their gut to be must shorter than ours is, relatively speaking.
Therefore although it's possible that softer stools might be caused by rapid transit times through the fish's GI tract, I bet it's actually the other way around. Since their gut is relatively short compared to their body length, it's likely that the consistency of the stool is indeed a function of 1) the food they're eating, and (I'll bet) more so 2) transit time through the alimentary tract. Also keep in mind that humans drink liquids, which will aid peristalsis and help keep stools more mobile. Freshwater fish are hypertonic compared to their environment, so they actually tend to have to expel water that gets absorbed across their skin through osmosis. In contrast, salt-water fish tend to lose fluids, as their blood is hypotonic with respect to their environment--so those fish have to "drink" water, which then gets desalinated by their gills. Point being that dietary liquid isn't likely going to influence the consistency of musky poop.
Anyway, that's enough. My head hurts and all this talk has made me hungry! | |
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Location: Hayward, Wisconsin | How about if they loose calories by expelling food before it is completely digested, it is compensated for by the additional intake of forage that is forcing it out??? | |
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| tcbetka - 12/19/2017 4:52 PM
Yes, but their feces isn't as "chunky" in the fall, remember? It's more bird-crap-like: Pasty and sticks to everything. It's the summer feces that's chunkier, according to the reports in this thread.
Tom, I think you might have mis-read or mis-remembered the earlier posts?
For example:
Will Schultz - 12/8/2017 1:45 PM
Could they be crapping all over your boat because the rate of digestion had slowed so much that they're eating beyond their digestive rate? Late fall muskie poop is very different from summer muskie poop and appears to be less digested (more scales, bones, etc).
That's my experience too - visibly less digested in the fall.
Larry Ramsell - 12/20/2017 7:16 AM
How about if they loose calories by expelling food before it is completely digested, it is compensated for by the additional intake of forage that is forcing it out???
Yes, that's the hypothesis that Will put forward and we are exploring, Larry: that if their rate of (chemical? enzymatic?) digestion is slowed in cold water periods, but the movement in the digestive tract remains the same, then they'd possibly be passing through food items before they can be completely digested. To make up for lost calories, especially to provide energy to their growing reproductive cells, they would actually need to eat more in the fall in spite of generally lower activity levels.
Observationally, the fall brings short, intense feeding windows, and not nearly as much of the following and other energy "wasting" behavior that you might see in the summer. Spawning baitfish concentrations would help this, as muskies wouldn't need to move as much to find the food.
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Location: Hayward, Wisconsin | But...they metabolize so fast in the summer, that it is impossible to know just how much forage is going thru their system...a real conundrum! | |
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Location: Green Bay, WI | I've clarified the post I had here--please see below.
Edited by tcbetka 12/21/2017 10:40 AM
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Location: Green Bay, WI | I had another thought (or two)...
First of all, I think that I was mistaken regarding the degree of decrease in gastric enzymatic activity as the water cools. If their preferred water temperature is around 70F, and we're fishing for them (in the fall) in water temperature of about 40F, then it's a swing of about 30F of cooling. So if enzymatic activity is cut in half for every 10F or so, then the rate of activity in the fall would be about 1/8th of that in the summer...give or take.
70F --> 60F = 1/2
60F --> 50F = 1/2
50F --> 40F = 1/2
Therefore: 1/2 * 1/2 * 1/2 = 1/8
So in all likelihood, they probably have a gastric enzyme rate of around 1/8th the rate of summer, when we're fishing for them in the fall. I didn't go back through the entire thread and read all my posts, but I believe I did the math wrong before. So I wanted to correct myself. This being said, it certainly supports a slowed rate of digestion in the fall.
Now then, in terms of the amount of feces we see them crapping out--I think that their intestines are more full in the fall, due to a combination of them 1) eating more (due to the opportunity) and 2) a *possible* delay in transit time through the bowel. I'm not convinced yet that their bowel slows significantly, for the reason(s) I mentioned in my post immediately proceeding this one. I think that the gastrocolic reflex is simply too strong for them to get (essentially) constipated because their body temperature is dropping. That wouldn't be good from an evolutionary standpoint.
Regarding how "chunky" their stool is or isn't in the fall, compared to the summer... I checked just now with my friend Jerry, and he indicated that he didn't see them crap in the boat as much in the summer as in the fall. That's my experience as well. I think they are eating more in the fall, so they have more waste in their intestine--so they crap more when they're handled. In terms of the consistency of said crap, I guess I can't really comment because I just haven't seen that much of it in the summer. In fact I also see more of it in larger fish, and I'm not used to catching larger fish in Green Bay in the summer. I think my average fish in the summer months out here is probably in the 42-43" range? I've never really kept track. But I will admit that when I was fishing a lot in the summer, it was NOT in the areas where guys have been catching big fish the past several years. I was sort of late to that party, and was concentrating more on the fall fishing areas, which (in my personal experience) didn't seem to have the bigger fish until Sept-Nov.
Edited by tcbetka 12/21/2017 10:24 AM
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| Do you suppose egg mass they are devolving in the fall could be compacting the digestive tract to the point where it effects the digestion process, so what whatever they eat is pushing out what they ate last time before it spends enough time in there to be fully digested? | |
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| Does a higher rate of dissolved oxygen in cold water vs summer months play a role in any of this? | |
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Location: Green Bay, WI | esoxaddict - 12/22/2017 4:26 PM
Do you suppose egg mass they are devolving in the fall could be compacting the digestive tract to the point where it effects the digestion process, so what whatever they eat is pushing out what they ate last time before it spends enough time in there to be fully digested?
Sort of the "pregnant women can't eat as much" idea? Hmmm, I suppose it's possible. To be honest I really don't know at what point the egg mass descends to the point where that might happen. I've never studied dead muskies throughout the egg-development cycle, so I can't say. I think my Larry would be the better guy to answer that question, as he's undoubtedly had more experience than me with that sort of thing.
Sudszee - 12/23/2017 8:57 AM
Does a higher rate of dissolved oxygen in cold water vs summer months play a role in any of this?
I'm not really sure I know what you're asking, but my take on it is that (to the degree possible) the fish will likely seek out water temperatures more to their liking in regards to the DO levels. In other words, I doubt they'll stay in water with low DO levels if they can help it. So in that sense, my answer would likely be "probably not". | |
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| fat belly don't exist .when i caught a perch,pike or walleye whit big belly and choose to filet them,there is not fat at all. i have never seen yet a ''fat'' belly,but i have seen eggs big meal in the guts but no fat lol | |
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| supertrollr - 3/8/2018 11:37 PM
fat belly don't exist .when i caught a perch,pike or walleye whit big belly and choose to filet them,there is not fat at all. i have never seen yet a ''fat'' belly,but i have seen eggs big meal in the guts but no fat lol
Never seen belly fat in any Esox, Eat very few any more. However in big walleye that feed primarily on alewives have seen a little belly fat on a few. But not like you might see in a salmon. | |
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