Monday, February 11, 2019

Species Profile: Rock Bass

As most of you hopefully already know, I am a life-list angler. I target, document, and count the number of species, hybrids, and subspecies I catch, specifically on fly tackle. Because of that I spend a lot of time learning about and fishing for many different species of fish. This means I'm more adept at identifying and fishing for an extremely broad range of species than the average fly angler. This series will attempt to outline species identification, some life history, and methods for targeting with fly tackle. Maybe I'll get to every fish on my life list, but considering it is ever growing... it would take a while. Mostly, I hope this will get a few of you interested in going out and learning about or catching something new. 

Rock bass, Abloplites rupestris, is an abundant sunfish species occupying a variety of water types. They are native to most pf the Midwest from the far east portions of the Dakota's east to the Lake Champlain watershed in Vermont and South to the very northernmost portions of Alabama and Georgia. They have been widely introduced outside of their range, including CT. In some areas where they were introduced they have wreaked havoc on native endemic species; including Roanoke bass, which are very similar, share the same niche, and can hybridize with rock bass; and an isolated population of trout-perch for which the extinction of was blamed on the introduction of rock bass.
Rock bass are generally less than 14 inches though individuals up to 16 and 17 inches have been recorded, rock bass as heavy as three pounds. An 8 inch fish is fairly typical. They may live as long as 10 years. These fish have a large mouth as sunfishes go, are deep bodied, generally golden to brown or olive in color with some dark spots and/or patches and a lighter colored belly. In the spring, when they spawn, their belly may darken, as in the large specimen below:

Six anal spines and frequently bright red eyes also help to distinguish rock bass. They can change their skin pigmentation in correlation with their surroundings so a broad range of colors and patterns exists within the species.

Rock bass are primarily carnivorous, eating other fish, insects, crustaceans, and small amphibians. They typically spawn from April through June around the time the water reaches 58 degrees. They spawn much in the same way other sunfish do, digging nests which they actively guard and frequently mate with multiple partners.

A prime location for rockbass in Vermont.

Rock bass are readily available to many anglers and are great sport on light fly tackle. They prefer clear-water lakes, rivers, and small streams, and are generally one of the most abundant species in the places they are found. Though they don't fight as hard as othe sunfish species, they do take topwater flies, streamers, and nymphs with aggression. The ideal setup is a 4wt rod with a weight forward floating line, and a 6 or 7ft leader tapering down to 3x. Small panfish poppers, Chernobyl ants, Woolly Buggers, small Clouser Minnows, and virtually any small streamer and any nymph pattern will dupe rock bass in different scenarios. I find sight casting to rock bass with nymphs in small rivers and streams and just twitching the fly in front of them to be very productive. In lakes and big rivers the effectiveness of a steady, slow figure 8 retrieve for any subsurface presentation is unparalleled.

Fish around rocky areas, as the common name of the species suggests. It is very possible to catch rock bass on the surface, especially in shallow water. But if you are interested in catching a really big rock bass it may be a good idea to swap out a floating line for a sink tip and fish larger Woolly Buggers or small Belly Scratcher Minnows on rocky structure in 10 to 20 feet of water. Targeting large rock bass can also be done during the spawn, when large fish move into the shallows to spawn.

Rock bass are a fun fish to target on occasion and they can also be very pretty. Go give them a shot when our lakes and rivers thaw out!

If you enjoy what I'm doing here, please share and comment. It is increasingly difficult to maintain this blog under dwindling readership. What best keeps me going so is knowing that I am engaging people and getting them interested in different aspects of fly fishing, the natural world, and art. Follow, like on Facebook, share wherever, comment wherever. Also, consider supporting me on Patreon (link at the top of the bar to the right of your screen, on web version). Every little bit is appreciated! 


  1. RM
    I can remember landing rock bass as a kid fishing some of the little streams near our home. I've landed a few on Smith Lake using tiny dries and poppers, which were under the 8" length. The fight wasn't as aggressive as the bluegill. Thanks for sharing

    1. They fight somewhere on par with crappies, bluegill definitely have them beat pound for pound.

  2. Love these posts of yours. I've enjoyed catching Rock Bass for years, but had never really investigated their "life" much. Had no idea they could get to 16-17" nor that they could morph coloration a bit, though that makes a lot of sense in hind sight. Cool stuff - thanks for the education.

    1. Thank you!
      Knowing the fish's life is an invaluable insight.

  3. Good read Rowan. We have a large creek that provides a good number of these little beauties and I have enjoyed catching them many times.
    Tie, fish, write, conserve and photo on...

  4. Those fellas love soft hackles.