Blue Largemouth Bass: Diet and Strange Colorations

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Fisher with Big Bass, blue sky, and lake!

Largemouth bass turn blue due to more fat in their diet. They may eat fattier fish like trout or small animals like ducks or mice with higher fat concentrations. As the fat levels increase in their body, largemouths change color and sometimes turn blue. 

Growing up, I fished in a pond that continuously produced largemouth bass that looked a little different than most of the fish in my area. I struggled to identify the difference until I caught one with my dad, and he called out its bluish tint. From then, I made sure to look closely at every bass I caught.

Largemouth Bass Diet

As humans, our diet is a significant factor in our appearance. Depending on what we eat, we appear healthy or unhealthy. The way we feel is tied into our diets as well. 

Bass change their appearance as their diet changes. Depending on what they eat, they gain or lose weight. In recent years, anglers have caught blue largemouth bass throughout some more common bass fisheries. 

Some anglers with private ponds and lakes also find blue largemouth bass. Scientists have concluded that largemouth bass turn a blue shade due to a higher-than-normal fat level in their diet. 

The higher amount of fat impacts their blood, changing their appearance. If bass have their traditional diet of crustaceans, smaller fish, insects, and amphibians, they have a lower chance of turning blue. 

Largemouth bass have a smaller chance of appearing their normal color in water where humans feed them. Most cases of blue largemouth bass show up in fisheries where humans feed them. 

Whether it’s pellets, leftovers, or anything that isn’t 100 percent natural, largemouth bass change color because of the food they eat. It’s a double-edged sword that humans face when they feed bass. Their survival may depend on humans feeding them, but that doesn’t mean they’ll be at their healthiest. 

A fisher with a rod waits for a fish.

Are Blue Bass Unhealthy? 

Blue bass are not unhealthy. They have higher fat concentrations but aren’t at risk of dying. If you catch a blue largemouth bass, take a picture and report it to your local game warden. It’ll be up to them to discuss the next steps. 

Biologists will run tests to determine the exact cause and what the fish need. 

If you have pet largemouth bass or bass in your private fishery and they’re turning blue, seek out the advice of a local wildlife biologist. They’ll be curious about what you’re feeding them and will recommend changes.

Like most things, changes happen and run their course, but if the fish look emaciated or seem sluggish, it’s time to be concerned. The sooner you report changes in conditions, the better chance you have of saving the fish. 

Largemouth bass chills in  spring, camera close!

Frequently Asked Questions

What Colors Do Largemouth Bass Come In? 

A normal largemouth bass is green, white, and black. Their bodies are green, their bellies are white, and a black stripe runs across them. Depending on the time of year and water conditions, their colors may change to be lighter or darker. 

What is the Rarest Color Bass? 

Blue and gold largemouth bass are the rarest colors. Most of the time, you’ll catch a traditional green, white, and black bass.


Catching any bass that isn’t the traditional color raises our curiosity levels. Our first instinct is to think something is wrong, but that isn’t always true. Bass go through different cycles, and their bodies change. Blue largemouth bass have more fat in their diet, but it doesn’t mean they’re unhealthy.

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