Growth and Survival of Hatchery-Produced Atlantic Sturgeon Released as Young-of-Year into the Hudson River, New York

Abstract

Abstract In 2007, a team of U.S. scientists performed a status review of Atlantic sturgeon Acipenser oxyrinchus oxyrinchus and concluded that the species would likely become endangered (U.S. Endangered Species Act 1973, as amended) in the foreseeable future over much of its range, including populations of the New York Bight, which is comprised of the Hudson and Delaware rivers. Therefore, we evaluated an experimental release of hatchery-produced Atlantic sturgeon that took place in 1994 to determine the value of using stocked fish as a population recovery tool. We obtained recapture data on hatchery fish (identified by presence of pelvic fin removal) from the Atlantic Coast Sturgeon Tagging Database. Our evaluation of retention for a pelvic fin removal mark on hatchery fish showed that 36% of clipped individuals retained a clean fin clip after 49 d. The minimum survival rate for hatchery fish to age 5 was estimated to be in the range of 0.49–0.66% using documented recaptures (N = 24), known number of fish stocked, and results of the pelvic fin removal evaluation. Length and weight-at-age for recaptured hatchery fish at known ages 5–17 were within the range of values reported for wild fish whose ages were estimated by pectoral spine analysis. We also report that one ripe male hatchery fish at age 15 was captured along with other spermiating males at its parental spawning area in the Hudson River in 2009.