PINE BLUFF - Elizabeth Heitman, a graduate student in the Department of Aquaculture and Fisheries at University of Arkansas at Pine Bluff, and her colleagues just completed an evaluation of supplemental stocking of fingerling largemouth bass into several pools of the Arkansas River. If proven effective, supplemental stocking could increase the numbers of bass available to anglers.

The first part of the study was an evaluation of Arkansas Game and Fish Commission stockings. In spring of 2002, about 50,000 2-inch fingerling largemouth bass were released into each pool of the river. Hatchery fish stocked in two of the pools were marked prior to release.

Arkansas Game and Fish Commission personnel and UAPB researchers sampled young bass from each of the two pools in fall of 2002 and spring of 2003 to see if the stocked fish had survived. Heitman found about 15 percent of the bass in that age class were from the previous spring’s stocking.

Researchers also wanted to know if larger stocked fingerlings would survive better in the river than smaller fingerlings. In spring of 2003, 2-inch and 4-inch largemouth fingerlings were stocked in a third pool, with the different sizes stocked in different coves.

Researchers released 2-inch fingerlings in June at 125 fingerlings per acre and 4-inch fingerlings in August at 25 fingerlings per acre. Bass in the coves were sampled in fall of 2003 and spring of 2004. During the two seasons, 2-inch and 4-inch stocked largemouth bass again contributed about 15 percent to the total bass population of that age. A cost analysis suggested it was less expensive to stock 2-inch fingerlings despite having to stock five times as many fish to achieve the 15 percent contribution to the total bass population.

This is the first evaluation of stocking size that has been conducted on a large river. The results are important because it was not known if the stocked fish would move out of the coves and disperse into other areas of the river. The results were similar to many studies where largemouth bass were stocked into lakes and reservoirs.

Although the study provided a good initial investigation of fingerling largemouth bass stockings into the Arkansas River, more work is needed over time to determine the long-term effects of supplemental stocking on the largemouth bass fishery. Additional research is needed to determine whether stocking fingerling largemouth bass every year would be necessary or only to supplement years when there are fewer largemouth bass.

“There are still several things that we do not know about these bass stockings," Heitman said. "For instance, we don't know if they will persist in the population as they grow older. It is also possible that stocked largemouth bass replaced some of the wild bass and didn't actually increase the size of that age group of bass."