Long-term evaluation of fitness and demographic effects of a Chinook salmon supplementation program

While the goal of supplementation programs is to provide positive, population-level effects for species of conservation concern, these programs can also present an inherent fitness risk when captive-born individuals are fully integrated into the natural population. In order to evaluate the long-term effects of a supplementation program and estimate the demographic and phenotypic factors influencing the fitness of a threatened population of Chinook salmon (Oncorhynchus tshawytscha), we genotyped tissue samples spanning a 19-year period (1998-2016) to generate pedigrees from adult fish returning to Johnson Creek, Idaho USA. We expanded upon previous estimates of relative reproductive success (RRS) to include two full generations and used generalized linear models to determine if origin (hatchery or natural) or phenotypic traits (timing of arrival to spawning grounds, body length, and age) significantly predicted reproductive success (RS) across multiple years. Our results provide evidence...

虽然增殖放流项目的目标是为受保护物种提供积极的种群层面效应，但当人工繁育个体完全融入自然种群时，这些项目也可能带来内在的适合度风险。为评估增殖放流项目的长期影响，并估算影响濒危奇努克鲑鱼（Oncorhynchus tshawytscha）种群适合度的种群统计与表型因素，我们对覆盖1998-2016年19年时间段的组织样本进行基因分型，以构建返回美国爱达荷州约翰逊溪的成鱼谱系。我们扩展了先前对相对繁殖成功率（RRS）的估算，纳入两个完整世代，并使用广义线性模型来确定来源（孵化场或自然环境）或表型性状（产卵场到达时间、体长及年龄）是否能在多年间显著预测繁殖成功率（RS）。我们的结果提供了证据...