Rock Bass vs Bluegill – What Is The Difference

By Get Fishing •  Published: 01/28/23 •  5 min read

If you’re new to experiencing the Sunfish family, you might be wondering how to tell so many species apart. While a quick glance may make it appear that there’s a lot of overlap, fish like the Bluegill and Rock Bass are actually distinctly different. We’re going to dig into what makes these two species special and how you can easily tell them apart.

rock bass vs bluegill

Is a Rock Bass the Same as a Bluegill?

The Rock Bass and Bluegill are not the same fish. These are two different species found within the Sunfish family, so while they do share some traits (like spiked fins), they’re also very unique. 

What’s the Difference Between Rock Bass vs Bluegill? 

The main differences between the Rock Bass and Bluegill have to do with the following:

We’ll get into each section in more detail later in this article.

What is a Rock Bass? 


The Rock Bass (Ambloplites rupestris) is a freshwater fish native to North America. It belongs to the Sunfish family (as does the Bluegill!). Rock Bass are often confused with other Sunfish, including the Warmouth, with whom they share a similar body shape. 

What is a Bluegill? 


The Bluegill can be considered one of the more “decorative” species within the Sunfish family. These fish are not only beautiful, but fun to catch, with a wide distribution that makes them easy to find if you know what you’re looking for. The Bluegill is also considered a panfish; they’re the perfect size for frying in a pan, though they don’t have much meat on them. 

How to Tell the Difference Between a Bluegill and a Rock Bass

The main differences between these species have to do with habitat preferences, where they can be found, and their appearance. Below we’ve highlighted some of these differences, beginning with physical characteristics. 

Rock Bass vs Bluegill Dorsal & Anal Spines

Rock Bass have 12 dorsal spines and 6 anal spines.

Bluegill usually have 10 spines, but can have anywhere from 9-11. They have only 3 anal spines.

The anal spines will be key in telling these two species apart, so keep an eye out when you’re hauling them in!

Rock Bass vs Bluegill Size Differences

The average Rock Bass is anywhere from 5-7 inches, but these fish easily reach up to a foot in length. Bluegills, on the other hand, are known for being small. They average 4-12 inches, but anything over 10 inches is considered “trophy” size, meaning it’s a rare catch. You’re more likely to find much smaller Bluegills ranging from 4-6 inches. 

Rock Bass vs Bluegill Coloration Differences

At first glance these two species might look similar. But Rock Bass are more commonly confused with the Warmouth or Smallmouth Bass. This is because they’re darker in appearance, with longer, less rounded bodies. Rock Bass are known for having red eyes and coloration ranging from golden brown to olive. Their bellies are very light in color.

Bluegill, on the other hand, are pretty to look at. These fish are a bit more saucer-shaped than the Rock Bass. Bluegill have blue-green bodies, but they’ve earned their name with the vibrant blue coloration on the gills. Their bellies are often orange-yellow. Bluegill also have a dark spot on the side of their “ears” and the rear of their dorsal fins. 

Rock Bass vs Bluegill Mouth Size

One of the most striking differences between these fish is their mouth size. Bluegills are known for having extremely small mouths, though it doesn’t make them any less hungry. Rock Bass, on the other hand, have noticeably larger mouths.

Where Can You Find Bluegill? 

fisherman holding a coppernose bluegill

Bluegill are one of the most widely distributed species in the Sunfish family. These fish can be found throughout the US, ranging from the east coast down to Florida, west to Texas, into northern Mexico, north to Minnesota and back east to New York.

Bluegill Fishing Tips

Fisherman holding a big bluegill

Bluegill aren’t a picky species, so you don’t need to worry about carrying the “right” tackle in terms of specific baits. Rather, you should make sure you have gear on hand that can stand up to Bluegill habitat – meaning jigs that can punch through vegetation and not get stuck, as well as a great casting reel. 

Bluegills are enthusiastic, but they’re small; you won’t need large hooks. Check out some of the options we’ve listed for the best Bluegill lures. 

Where Can You Find Rock Bass? 

Rock Bass have a much smaller range than the Bluegill. They are native to the Mississippi drainage and can be found in offshoots of this water source throughout the northeast and southeast. This species is well-liked enough that some anglers have also decided to stock them in unlikely water sources along the Atlantic coast.

Rock Bass Fishing Tips

What is a rock bass

Habitat is important when fishing for Rock Bass. This species will avoid fast-moving water, so look for calm water sources. Rock Bass will hang out near the banks, and you should be prepared with gear that won’t get hung up on obstacles in shallow areas of water. Like the Bluegill, Rock Bass aren’t picky about what they eat. They’re opportunistic eaters and anything that catches their eye (including flashers and poppers) is a potential meal. Get creative and pay attention to where you’re fishing over what you’re fishing.


While it’s easy to see how these fish may occasionally get confused, their habitat preferences and physical characteristics go a long way in making them individuals. Keep a close eye on habitat, range, and coloration, and you’ll quickly become a pro at telling Rock Bass apart from Bluegill!

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