Shoal Bass Study

Photo of small shoal bass

Shoal bass, unlike largemouth, have no lateral band and tiger-like markings. They have scales on the base portion of the second dorsal fin. The first and second dorsal fins are clearly connected, and the upper jaw does not extend past the back edge of the eye.

The Black Bass Management Plan incorporates all five black bass species found in Florida. Even though the ever-present Florida largemouth black bass gets most of the attention from anglers, due to its trophy-size potential and wide range, the other four species offer unique challenges both to managers and anglers. To managers, their limited range, and specific habitat requirements make for an ongoing concern that a single-event such as a hurricane, chemical spill, disease outbreak or drought that reduces flow below minimum requirements could have significant consequences. New research is helping the Florida Fish and Wildlife Conservation Commission (FWC) improve management options.

These species are doing reasonably well and are of interest to anglers looking for a unique experience, often in near pristine areas, or wanting to complete a “slam.” The FWC for instance, recognizes a “Bass Slam” for catching a largemouth, spotted, shoal, and Suwannee bass within one year. There are no minimum size requirements to report an FWC Bass Slam (see MyFWC.com/BigCatch). BassMaster magazine has a different Bass Slam that includes all nine species of black bass found in North America. They have no time limit, but each fish must exceed a minimum total length, be photographed and released (see Bassmaster.com/slam).

Shoal bass Micropterus cataractae are one of the unique black bass species. They occur in a limited range of limestone shoals in the upper Chipola River of northwest Florida. Shoal bass are included in northwest Florida’s five black bass aggregate bag limit, with a 12-inch minimum size.

A five-year study (2007-2011) of shoal bass evaluated the status and trend of shoal bass stocks. This research greatly contributed to what is known about this species and provides the science-informed background necessary for the FWC to continue to assess and manage this species. Population and life history dynamics were evaluated, including population estimates, length frequencies, total annual mortality estimates, age and growth, and diet. Population estimates, as an example, required bass to be sampled using non-lethal electrofishing techniques marked-and-released and then recaptured. A few bass were sacrificed, so their age-and-growth rate could be calculated using marks on the fish’s otoliths (ear bones), much like counting tree rings. Stomach contents were also examined to determine what they ate.

In addition, creel survey estimates, which involve talking to anglers about what they are trying to catch, how long they spend fishing, how many fish they catch, and whether or not they release their catch, provide practical information on the fish population and recreational use. A standard length-weight equation was developed, to allow an estimate of a shoal bass’ weight based on its length. This information came from three river sections that allowed comparisons between shoals, riffles, runs and pool areas containing limestone outcropping.

Results show a robust population of shoal bass with the highest ratio of shoal to largemouth bass in the Peacock Bridge to Johnny Boy Landing section. Diets of shoal and largemouth bass were similar and consisted primarily of crayfish followed by fish. The creel survey revealed anglers primarily targeted bream in this area. Anglers seeking shoal bass often used small crawfish-type crankbaits, three-inch jerk-baits, or small spinner baits or jigs. Fishing was best around riffles and deep pools immediately upstream and downstream of limerock shoals.

The FWC will continue to monitor the well being of all black bass species in Florida and relies heavily on studies such as these to determine what is needed to protect and enhance critical habitats, the genetic health of the species and recreational opportunities.

For more information, contact Chris Paxton, 850-488-0520; Chris.Paxton@MyFWC.com.



FWC Facts:
Florida bass build nests for spawning and protect their young until they reach about 1 inch in size.

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