Growth seen with Chipola’s depleted shoal bass

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Adult shoal bass nurtured at a Blackwater hatchery have led to a rebound of this unique population in the Chipola River, devastated by Hurricane Michael.

At next week’s Florida Fish and Wildlife Conservation Commission’s meeting, staff plans to give an update on their efforts to restore the shoal bass population in the river. 

No action is set to be taken on the presentation by Christopher J. Paxton, regional fisheries administrator, slated for Thursday morning, July 14, at the Adam W. Herbert University Center in Jacksonville. That presentation could be moved or postponed, according to the agenda notes.

In a summary memo, Tom Graef, director of freshwater fisheries management, wrote that he plans to inform commissioners of successes in shoal bass conservation since the 2019 regulation change post-Hurricane Michael, which had impacted the adult shoal bass population in the Chipola River by over 90 percent.

“The Chipola River, located in the Panhandle, is home to the only known reproducing, genetically pure population of shoal bass,” he wrote.

FWC took proactive regulation action by prohibiting both possession and harvest of shoal bass.

“Staff also utilized stocking of genetically pure shoal bass to supplement and protect the genetic purity of the wild shoal bass population,” he wrote.

Shoal bass (Micropterus cataractae) are one of the least common black bass species found in Florida and have been identified as a Species of Greatest Conservation Need in both Florida and Georgia. Graef said this designation is a result of their limited habitat range, decreasing habitat availability, and potential for genetic hybridization. 

Previous management actions resulted in a portion of the river containing critical shoal bass habitat being designated as a FWC conservation zone in 2016 to help protect this population.

“Hurricane Michael struck the Panhandle region of Florida in Oct. 2018 causing tremendous destruction,” he wrote. “The Chipola River drainage basin was affected by large-scale damage to the tree canopy habitat along the river, large amounts of silt washing into the river, and numerous ruptured wastewater and sewer lines discharging into the river. 

“These impacts resulted in widespread fish kills and the destruction of a significant amount of critical shoal bass habitat. Post-storm surveys in May 2019 revealed a greater than 90 percent decline in the adult shoal bass population,” Graef will report.

A June 2019 Executive Order prohibited the harvest and possession of any shoal bass, and that order was subsequently incorporated into rule at the Dec. 2019 FWC meeting. 

“Staff also collected and maintained a small group of adult shoal bass as broodstock at the

Blackwater hatchery,” he wrote. “Through several production trials over the last two years, staff was successful in spawning this riverine species in hatchery ponds in spring 2022. This success resulted in the return of approximately 3,300 shoal bass fingerlings to Chipola River in May 2022.

“Through proactive conservation management actions, innovative hatchery production techniques, and internal cross-collaboration, staff are working to ensure the shoal bass population recovers to the level that anglers can once again enjoy this vibrant and valued bass species for years to come,” Graef wrote.

Shoal bass are similar in body shape to largemouth bass, although the upper jaw does not extend beyond the back edge of the eye as it does on largemouth bass, Also, in largemouth, the spiny first dorsal fin is separated from the soft dorsal fin, which does not have scales. On the shoal bass, there are scales on the base portion of the soft dorsal fin, which is connected to the spiny dorsal by a thin piece of skin. 

Shoal bass have vertical stripes above the midline of the body; they resemble tiger stripes and help distinguish them from other black bass in Florida,

Although historically found in the Apalachicola River, habitat degradation has all but eliminated shoal bass from the river proper. As their name implies, shoal bass favor “shoal" type habitats that include shallow, fast moving riffles and runs containing limestone.

Chipola River, adult, shoal, bass

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