Time-series analysis reveals genetic responses to intensive management of razorback sucker (Xyrauchen texanus)

Time-series analysis is used widely in ecology to study complex phenomena, and may have considerable potential to clarify relationships of genetic and demographic processes in natural and exploited populations. We explored the utility of this approach to evaluate population responses to management in razorback sucker, a long-lived and fecund, but declining freshwater fish species. A core population in Lake Mohave (Arizona-Nevada, USA) has experienced no natural recruitment for decades, and is maintained by harvesting naturally produced larvae from the lake, rearing them in protective custody, and repatriating them at sizes less vulnerable to predation. Analyses of mtDNA and 15 microsatellites characterized for sequential larval cohorts collected over a 15-year time series revealed no changes in geographic structuring, but indicated significant increase in mtDNA diversity for the entire population over time. Likewise, ratios of annual effective breeders to annual census size (Nb/Na) incr...时间序列分析（time-series analysis）已广泛应用于生态学领域以探究复杂自然现象，且在阐明自然种群与开发利用种群的遗传及种群动态过程间的关联方面具备可观应用潜力。本研究旨在评估该方法在锐背吸口鱼（razorback sucker）种群管理响应效果研究中的应用价值。锐背吸口鱼是一种寿命长、繁殖力强但种群数量持续下降的淡水鱼类。美国亚利桑那州-内华达州境内莫哈韦湖的核心种群数十年来未发生自然补充，其种群维持依赖于从湖中采集天然产出的幼鱼，经人工保护性繁育后，将体型已降低被捕食风险的个体放归原水域。研究人员对15年时间序列中采集的连续幼鱼世代开展线粒体DNA（mtDNA）与15个微卫星标记（microsatellites）分析，结果显示种群的地理结构未发生显著变化，但整个种群的线粒体DNA多样性随时间呈现显著上升。同样，年度有效繁殖种群数与年度普查种群数的比值（Nb/Na）呈上升趋势……