Nothing feels as good as the ice thawing on a lake, the sun beginning to shine for longer days, and the first bass of a new year. But when you pull out the first few bass in the late winter or early spring, you may notice that their lips and throat are a vibrant red. Is there something wrong with the bass you just caught?
No, this is absolutely normal and happens at most every fishery.
But why are bass’s lips and throats red at this time of the year? Honestly, we still don’t have a verified answer. But lets look into all of the possible theories below and see which seem the most plausible. And I’ll explain which theory I support.
Bass eating crawfish makes them turn red
The answer that most fisherman have told me throughout the years is that bass get red lips because they are eating crawfish. The pigmentation in crawfish leave red marks in a fish’s mouth when they are exclusively feeding on them. Or their pinchers can cause irritation in the fish’s mouth, which makes the red coloration.
First, I’ll speak to the merit of this argument. In the late winter bass are feeding most heavily on crawfish. This is mainly due to low water temperatures which make fish less likely to chase schools of shad or other bait sources. Instead, they sit close to the bottom of lakes and eat mainly the crustaceans moving around the bottom which require less energy to hunt and provide a better “bang for your buck” option as far as protein.
Also, crawfish like many other food sources will leave some pigmentation in the mouth of whatever is eating them. This is not an unusual thing for many food sources, and I’m sure you can think of a few things you eat that may leave your mouth a certain color for a period of time. And sure, if a crawdad pinches you, the blood flow to that area will increase and cause red streaks.
So does it make sense as a theory? Yes, but with some really big holes that I would like to point out…
Not every fishery has crayfish. In fact, many of the local ponds here in Virginia do not have them at all. Or at least, I’ve never seen them and I go fishing quite a bit. Yet, when I pull out any bass from these ponds in the middle of March, they have bright red lips and red marks in their gills and throats. Am I really to believe they are eating so many crawdads that their mouths are red but I’ve just somehow never seen one? I don’t think so.
Further, if you inspect the bass with red lips you’ll almost always see the pigmentation change in very similar places and in very specific patterns. The lips, gills, and throat are always a bright red in small patches. If it really is caused by crawdad claws or pigmentation, why is it the very same areas of a fish that are red and not just random areas where the fish has inhaled them?
And more importantly, why would their LIPS be red? If you have ever seen a bass eat anything, they hardly ever let their lips touch their food. They simply inhale their sources in their “large mouth” and don’t actually chew with their lips like a human. So why would their lips be a bright shade of red? It doesn’t make any sense to me.
Finally, if crayfish diets do turn a bass’s mouth red as described, why do we only see bass with red mouths for a month or two out of the year? After the late winter, early spring period most bass will return to normal. I don’t know about you, but I catch plenty of bass on crawdad imitations throughout the year. So if they’re eating crayfish all year, why would their mouths only be red for a couple of months? Again… something just doesn’t add up to me.
So while I won’t argue that a crayfish diet can turn a bass’s mouth red in some cases, I am very certain it is not the reason that bass have red mouths in the late winter and early spring. So lets look at another theory.
Spawning makes bass have red lips
A less common theory that I’ve heard is the act of spawning causes bass’s mouths to turn red. It is known that bass will move up to shallow areas to spawn and create beds for females to lay eggs. This includes using their entire bodies to clear out the bottom areas of any debris, making a nice space for the female to lay eggs. This can include using their lips to move things. It is very well known that bass may have bloody tails from beating it into the bed to clear out areas, so why not their lips as well?
This makes some sense, but also is not a theory I believe in. Mostly because I have caught plenty of female bass with red lips. Females get a noticeable “gut” in the late winter and early spring due to the eggs they are carrying and are easily identifiable. Males are the bed-makers, and females are the egg layers. So there is no reason they would have red mouths from making beds.
I’ve also caught bass well before spawn had even begun and found them with bright red lips. They were sitting in over 10 feet of water, making it nearly impossible for them to be making beds for spawn as they’re usually well within 2 feet. And how would their gills and throats be red unless they’re eating the lake bottoms they’re trying to clear? Again… I don’t think this is the answer either
Pressure Change causes bass red lips
Another theory is that the red color comes from pressure changes as the bass move from their deep water hideouts for the winter and early spring months and then start to move shallower slowly. Some argue that the holding in deep water causes the red rashes due to the pressure put on the fish in deeper water. Others argue it starts as the move shallower and it’s the pressure change that causes bass to react this way.
I’m frankly not a scientist and can’t answer this one with any validity. But I’ll say it makes sense in that we do see some other changes in bass during the winter months as they go deeper. Largemouth bass turn extremely pale as they hold in their deep water haunts in the winter. When you catch one, you might be extremely surprised as much of their green coloration is gone. However, as they move shallower again their pigmentation comes back quickly and they look like the green and white mixture that we are used to seeing throughout the rest of the year.
So there is a precedent that is known to anglers that fish change color based on where in the water they are holding and the temperature of the water. It’s also believed this coloration is caused by the sunlight penetrating the water, which doesn’t happen when bass hold deep under the water making them turn pale.
Is it created by pressure, temperature, or a combination of the two? I’m not so sure. I will say that bass will hold in just as deep of water in the middle of summer and I don’t notice them as white as they are in the winter. I also don’t find bass to have red lips, gills, or throats in the summer even though they may be in just as deep of water. So the pressure change alone doesn’t seem like the answer to me, though it may be part of the real answer.
Water temperature and bass color
Now we finally get to the theory for why bass have red lips during the late winter and early spring that I actually believe in. The water temperature causes some sort of reaction that turns certain areas of the bass red.
There have been no scientific studies to test this, but it is the only possible solution that makes sense. We’ve pointed out above the flaws in all other theories, but we know two things. This happens for bass in all types of water systems and happens during one time of year – from winter into spring. And the one thing that is in common is that the water is as cold as it will ever be. So that must trigger something that makes the bass lips red.
If you ever feel the area on a bass which turns red, you’ll also feel that the texture on those parts of the skin are a little different than the rest of their body. While bass don’t have “teeth” in the normal sense, it is a tough area with lots of rough edges that are similar to what you would think of as teeth. There is something for this one part of the bass’s body that turns red when the water gets cold.
It’s a simple solution, but the one that makes the most sense. It also coincides with bass turning white in the cold, another known color-changing phenomena in the species. The only real question is why this doesn’t happen during the fall transition when water cools? You’ll only see red lips on bass during the late winter months when water is at its coldest and starts to get warmer. Why when it goes from warm and gets cooler you don’t see the progression is still unknown. My guess is simply that the water temperature change is not as drastic, so doesn’t cause the immediately noticeable red coloration on the lips and throat.
There are likely more theories, and I would be happy to learn of any you have heard and research it’s probability. Looking at all of them and the evidence we have, it’s clear that bass getting red lips is mainly caused by water temperature. While eating crawfish, spawning, and other theories might explain some discoloration it does not explain the bright red lips many bass get in the late winter and early spring. But if you have a different opinion or know of another theory leave it below!
If you liked this article, read some of our most popular articles below!