Understanding fish-habitat associations and distributions are important for making informed management decisions relevant to habitat restoration and species recovery. Chinook salmon, in particular, rely heavily on estuaries, and restoring these habitats has become an important component of recovery plans for threatened populations. Information regarding general distribution patterns, while often lacking, could be useful for restoration evaluation and planning. We used time series analysis to identify common trends in weekly Chinook salmon abundance among seven separate zones within the Snohomish River delta while evaluating the effect of temperature and outmigration abundance on observed patterns. We found two unique trends described seasonal Chinook salmon density and a significant negative effect of temperature on observed density throughout the estuary. The first trend indicated Chinook salmon density increased steadily from February through early June before decreasing into mid-summer. The second trend was characterized by an early spike and a gradual increase in density into early April before leveling off then decreasing into mid-June. The association of each zone with these trends was consistent with the distribution of tidal wetland habitat area among each zone. We postulate that these trends in seasonal Chinook density reflect patterns of movement and rearing, respectively, throughout the estuary and highlight how and where estuary habitat in the Snohomish delta supports life history diversity. Confirmation of seasonal rearing patterns may aid current restoration project evaluation, while a migratory seasonal trend may help prioritize future restoration in the Snohomish estuary by identifying where opportunity exists to support estuary rearing for Chinook salmon. Finally, our methodology and analytical approach for evaluating spatial and temporal variability in Chinook salmon distributions and abundance may be applied to other tidal deltas to make informed decisions or evaluations of both current and future restoration actions.

了解鱼类栖息地的关联和分布对于做出与栖息地恢复和物种恢复相关的知情管理决策很重要。特别是奇努克鲑鱼，严重依赖河口，恢复这些栖息地已成为受威胁种群恢复计划的重要组成部分。关于一般分布模式的信息虽然经常缺乏，但对恢复评估和规划很有用。我们使用时间序列分析来确定斯诺霍米什河三角洲七个独立区域中每周奇努克鲑鱼丰度的共同趋势，同时评估温度和外迁丰度对观察模式的影响。我们发现两个独特的趋势描述了季节性奇努克鲑鱼密度和温度对整个河口观察到的密度的显着负面影响。第一个趋势表明奇努克鲑鱼的密度从 2 月到 6 月初稳步上升，然后下降到仲夏。第二个趋势的特点是早期高峰和密度逐渐增加到 4 月初，然后趋于平稳，然后下降到 6 月中旬。每个区域与这些趋势的关联与每个区域之间潮汐湿地栖息地面积的分布是一致的。我们假设季节性奇努克密度的这些趋势分别反映了整个河口的运动和饲养模式，并突出了斯诺霍米什三角洲的河口栖息地如何以及在何处支持生活史多样性。确认季节性饲养模式可能有助于当前的恢复项目评估，而季节性迁徙趋势可能有助于确定斯诺霍米什河口未来恢复的优先顺序，因为它可以确定支持大鲑鱼河口饲养的机会。最后，我们用于评估奇努克鲑鱼分布和丰度的时空变异性的方法和分析方法可应用于其他潮汐三角洲，以对当前和未来的恢复行动做出明智的决定或评估。