https://aurora.auburn.edu/handle/11200/3981 Wed, 10 Jun 2026 21:11:48 GMT 2026-06-10T21:11:48Z https://aurora.auburn.edu/handle/11200/50817 Evaluating the Genetic Response Following Introduction of Florida Largemouth Bass into Two Large Arkansas Reservoirs The Florida largemouth bass (FLMB; Micropterus salmoides floridanus) is widely stocked throughout the southeastern United States with the intent of increasing the size potential of resident northern largemouth bass (NLMB; M. s. salmoides) populations. During the early 2000s the Arkansas Game and Fish Commission initiated an eight-year FLMB stocking program on selected reaches of DeGray Lake and Lake Ouachita in an effort to sat- isfy angler preferences. The goal of this stocking program was to achieve 40% of sampled largemouth bass in each introduction zone possessing FLMB alleles by the end of the program. To assess this, fin clips were removed from hundreds of largemouth bass collected both within the stocking area as well as three areas distant from the stocking area of each reservoir. Fin clip samples were collected before, during, and after the stocking program and microsatellite analysis was used to evaluate temporal trends in the percent contribution of FLMB and F1 hybrids as well as the overall shift in genetic composition. Both reservoirs met the a priori standard of success after five years of stocking in Lake Ouachita and seven years in DeGray Lake. How- ever, the majority of fish collected near stocking sites at the end of this study contained relatively low levels of FLMB alleles (q range = 0.649 to 0.886) and very few F1 or FLMB were collected during the study. Therefore, we suspect that these fish contributed little to angler catch in these systems. This stocking was successful in creating high abundances of FX-NLMB, but future work is needed to know if these individuals enhance the population size structure or improve angler satisfaction. https://aurora.auburn.edu/handle/11200/50817 https://aurora.auburn.edu/handle/11200/50816 Spatial Patterns of Florida Largemouth Bass Genetic Introgression into a Northern Largemouth Bass Population after Stocking To enhance trophy potential of largemouth bass (Micropterus salmoides) fisheries, state agencies across the southeastern United States commonly stock Florida largemouth bass (FLMB, M. s. floridanus) outside of their native range into native northern largemouth bass (NLMB, M. s. sal- moides) populations. This practice has been ongoing for decades but spatial patterns associated with the spread of FLMB alleles in a reservoir after stocking are not well understood. From 2007–2015 the Arkansas Game and Fish Commission stocked 250 FLMB fingerlings ha–1 into two embayments of Lake Ouachita, a 16,200-ha highland reservoir in western Arkansas. In 2019, we collected 1000 largemouth bass from throughout the reservoir to examine spatial patterns of FLMB introgression using a panel of 35 species-diagnostic single-nucleotide polymorphisms (SNPs). We determined that 30.4% of individuals were NLMB and 69.6% were hybrids of NLMB and FLMB, with no FLMB collected. Average % FLMB alleles across all individuals collected was 11.4%. Spatial analyses found that FLMB alleles were greater in individuals collected in close proximity to stocking areas and then east- ward through the main body of the reservoir. Conversely, FLMB alleles were lower in the western half of the reservoir. Our results provide evidence that localized stocking of FLMB at high densities into a resident NLMB population can lead to widespread genetic shifts even in very large systems, but that most individuals in those systems contain low levels of FLMB alleles. https://aurora.auburn.edu/handle/11200/50816 https://aurora.auburn.edu/handle/11200/50815 Age and Growth Comparison of White Bass Among Three Southeastern U.S. River-Reservoir Systems White bass (Morone chrysops) are a popular sport fish native to the Mississippi River basin and widely introduced elsewhere. We examined population characteristics of this species in three systems (Kentucky Lake, Tennessee; Tennessee-Tombigbee Waterway, Mississippi; and Grenada Lake, Mississippi) with different habitats and fishery characteristics to evaluate whether population dynamics varied sufficiently to require system-specific management. Using white bass collected from these three systems in 2019–2020, we tested two aging techniques and found sectioning of otoliths provided more precise age estimates compared to using whole otoliths. We collected white bass up to 9 years of age, representing the oldest maximum age reported for southern populations. However, populations were composed of mostly younger fish, with 84% four years old or younger. All fish reached preferred size (300 mm TL) by age 3 across study areas. We found differences in length-at-age among populations, but we do not believe that these differences were large enough to justify system-specific management regulations. https://aurora.auburn.edu/handle/11200/50815 https://aurora.auburn.edu/handle/11200/50814 Experimental Population Reduction of Largemouth Bass from an Overpopulated Tropical Reservoir: Impacts on Predators and Prey Behavioral shifts by bass (Micropterus spp.) anglers toward catch and release practices has severely decreased the ability of managers to control predator-prey dynamics and reduced effectiveness of harvest as a management tool. Lack of harvest reduces managers’ ability to use harvest regulations to influence bass growth and can result in slower growth and poor condition due to excessive predator abundance and reduced prey availability. This scenario appears to have developed in a tropical reservoir where angler harvest has been limited. Largemouth bass (M. nigricans) were experimentally removed from Cerrillos Reservoir, Puerto Rico, to test if targeted population reduction could improve prey availability and condition of largemouth bass in tropical systems. Specific objectives were to 1) assess the response of prey species abundance and size distributions to reduced predator abundance, and 2) determine the response of largemouth bass size structure and relative weight to experimental population reductions. The experimental removals resulted in increased abundance and decreased mean size of sunfish (Lepomis spp.) and tilapia (Coptodon and Oreochromis spp.) as recruitment of prey species increased. Abundance of threadfin shad (Dorosoma petenense) also increased. Largemouth bass Wr increased, indicating improvement in prey availability and improved predatory success. However, recruitment of largemouth bass also increased, highlighting the need for harvest, either by anglers or managers, to maintain population abundance necessary to maintain improvements in size-structure and condition. https://aurora.auburn.edu/handle/11200/50814