First evidence of natural reproduction and recruitment of reintroduced Lake Sturgeon in the Coosa River, Georgia

Abstract

Objective Lake Sturgeon Acipenser fluences became extirpated from the Coosa River system in Georgia and Alabama during the 1970s. The Georgia Department of Natural Resources began stocking hatchery-raised Lake Sturgeon in 2002 with the goal of reestablishing a self-sustaining population. Stocking lapsed in 2020 due to the COVID-19 pandemic, which allowed an opportunity to assess natural recruitment to the reintroduced population. Methods We conducted trammel-net surveys during May–August in 2022 and 2023 and removed a pectoral fin spine section from all captured individuals. We compared the fin spine sections of suspected naturally hatched juveniles with those from known-age, hatchery-raised juveniles to confirm our age estimates. Results We captured one age-2 juvenile Lake Sturgeon in 2022 and eight age-3 juveniles in 2023. This indicates the presence of natural recruitment due to the absence of stocking of hatchery individuals in 2020. Conclusions Documenting individuals of a year-class that was not created by hatchery-raised juveniles provides the first evidence that offspring of early reintroduced Lake Sturgeon are being recruited into the reintroduced population in the Coosa River, Georgia.