The Alaska salmon hatchery program is intended to supplement salmon fisheries without supplanting wild stocks. Hatchery-origin Chum Salmon Oncorhynchus keta spend most of their lives interacting with wild salmon, including some degree of straying to spawning streams. Our study was designed and implemented to measure the extent and annual variability of straying by hatchery-produced, summer-run Chum Salmon in Southeast Alaska from 2013 to 2015 by sampling in individual streams to estimate the proportion of hatchery strays. In the sampled index streams, the proportion ranged from 0.000 to 0.854 over the 3 years. Unbiased estimates of the proportions of hatchery-origin fish spawning in each of the three management units ranged from 0.016 to 0.081, and the estimated hatchery proportions spawning across Southeast Alaska ranged from 0.032 to 0.060. The proportion of hatchery strays decreased as the distance from hatchery release sites increased; proportions were highest at streams located within 50 km of the nearest release site. The proportion of hatchery-origin spawners was negatively related to the index of spawning escapement in a stream. A hatchery donor stray rate of 0.8–4.8% was estimated. Hatchery-origin Chum Salmon occur at low levels in most Chum Salmon systems in Southeast Alaska and at higher levels in systems close to hatchery release sites.

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2013-2015 年阿拉斯加东南部夏流鲑鱼擒纵系统中孵化鱼的比例

阿拉斯加鲑鱼孵化场计划旨在在不取代野生种群的情况下补充鲑鱼渔业。孵化场原产的鲑鱼Oncorhynchus keta他们一生的大部分时间都在与野生鲑鱼互动，包括在一定程度上误入产卵溪流。我们的研究旨在测量 2013 年至 2015 年阿拉斯加东南部孵化场生产的、夏季运行的鲑鱼的误入程度和年度变异性，方法是通过在个别溪流中取样来估计孵化场的离群比例。在抽样的指数流中，3 年的比例从 0.000 到 0.854 不等。三个管理单位中每一个的孵化场产鱼比例的无偏估计范围为 0.016 至 0.081，阿拉斯加东南部的孵化场产卵比例估计范围为 0.032 至 0.060。随着离孵化场放生地点的距离增加，孵化场流浪的比例下降；在距离最近的释放点 50 公里范围内的溪流中比例最高。孵化场产卵者的比例与溪流中产卵逃逸指数呈负相关。孵化场捐赠者的流浪率估计为 0.8-4.8%。孵化场原产的鲑鱼在阿拉斯加东南部的大多数鲑鱼系统中含量较低，而在靠近孵化场放生地点的系统中含量较高。