Zona Jacob O, Kreiser Brian R, Kaeser Adam J, Fox Adam G, D'Ercole Mark J
School of Biological, Environmental, and Earth Sciences, University of Southern Mississippi, Hattiesburg, Mississippi, United States of America.
Panama City Fish and Wildlife Conservation Office, United States of America Fish and Wildlife Service, Panama City, Florida, United States of America.
PLoS One. 2025 Jun 3;20(6):e0319117. doi: 10.1371/journal.pone.0319117. eCollection 2025.
The Gulf sturgeon (Acipenser oxyrinchus desotoi) is a large, long-lived, anadromous fish inhabiting the northern Gulf of Mexico. This charismatic fish was hunted to near extinction in the early 1900s. In 1991 the subspecies was listed as threatened under the Endangered Species Act. Recovery continues to be challenged by threats such as habitat destruction, fisheries bycatch, and climate change. There are seven known natal rivers. Historically, each river was thought to contain a single, spring-spawning group. Recent studies have discovered several rivers (Suwannee, Choctawhatchee) contain a second, fall-spawning group. This study utilizes genetic techniques to investigate the proposed existence of a fall-spawning group in the Apalachicola River, Florida. Juvenile Gulf sturgeon were sampled between May and July, from 2013 to 2022. Four adults were also captured on the spawning grounds during October of 2022. Samples were genotyped for thirteen microsatellite loci to assess genetic population structure within the Apalachicola River. Analyses detected two distinct genetic groups (FST = 0.085). Dates of capture, length frequency distributions of juveniles, and genetic assignment of spawning adults allowed us to characterize these as separate spring- and fall-spawning groups. While approximately 90% of juveniles collected were assigned to the spring, only slight differences in genetic diversity were detected between groups. The temperature window for spawning was found to be three weeks shorter on average in the fall than the spring, highlighting the need for additional research into differing environmental or anthropogenic influences on these populations. The discovery of a fall-spawning group of Gulf sturgeon in the Apalachicola River improves our understanding of the representation, redundancy, and resiliency of the species and provides critical information for improved management of this river system.
海湾鲟（Acipenser oxyrinchus desotoi）是一种大型、长寿的溯河洄游鱼类，栖息于墨西哥湾北部。这种具有魅力的鱼类在20世纪初因过度捕捞而濒临灭绝。1991年，该亚种被列入《濒危物种法》的受威胁物种名单。由于栖息地破坏、渔业兼捕和气候变化等威胁，其种群恢复仍然面临挑战。已知有七条产卵河流。历史上，每条河流都被认为只包含一个春季产卵群体。最近的研究发现，几条河流（苏万尼河、乔克托哈奇河）还存在第二个秋季产卵群体。本研究利用基因技术调查佛罗里达州阿巴拉契科拉河中是否存在秋季产卵群体。2013年至2022年5月至7月间采集了幼年海湾鲟样本。2022年10月，还在产卵场捕获了四条成年海湾鲟。对样本的13个微卫星位点进行基因分型，以评估阿巴拉契科拉河内的遗传种群结构。分析检测到两个不同的遗传群体（FST = 0.085）。捕获日期、幼鱼的体长频率分布以及产卵成年鱼的基因归属，使我们能够将这些群体分别表征为春季和秋季产卵群体。虽然收集到的幼鱼中约90%被归为春季群体，但两组之间的遗传多样性仅检测到细微差异。结果发现，秋季产卵的温度窗口平均比春季短三周，这凸显了需要进一步研究不同环境或人为因素对这些种群的影响。在阿巴拉契科拉河中发现海湾鲟秋季产卵群体，有助于我们更好地理解该物种的代表性、冗余性和恢复力，并为改善该河流系统的管理提供关键信息。
