Assessing gulf sturgeon recruitment in the Apalachicola-Chattahoochee-Flint River basin

Abstract

Gulf Sturgeon, Acipenser oxyrinchus desotoi, were historically abundant across Gulf Coast rivers from Florida to Louisiana. Overfishing and habitat fragmentation during the 1900s resulted in population declines leading to its listing under the Endangered Species Act in 1991. Currently, the population in the Apalachicola-Chattahoochee-Flint (ACF) drainage is at a fraction of historic levels, largely attributed to the construction of a dam blocking access to 78% of riverine habitat. From 2013-2015, I conducted a study to assess current recruitment in the ACF drainage and identify habitats that are important to recruitment, and hence recovery of this population. I used mark-recapture to provide yearly estimates of age-1 abundance. I also used acoustic telemetry to determine habitats important to juvenile cohorts and assess the potential benefits to recruitment from adult passage above the dam. The results of this study provide insight towards management actions that could improve the status of this population.