Three decades of research on migration timing, growth, and survival of the most remote wild Chinook salmon populations in the Continental USA

From 1992-2022, NOAA fisheries has PIT tagged 321,623 juvenile wild Snake River spring/summer Chinook salmon throughout the Salmon River basin and monitored migration timing, growth, and estimated parr-to-smolt survival of individual populations. Fish were collected in late summer (July – September) and tagged in up to 16 study sites. As the fish migrate from study sites to Lower Granite Dam (LGD), data is collected on in-stream PIT arrays (ie Valley Creek) and again at LGD allowing the calculation of tributary segment survival, stream segment survival, arrival timing, and parr-to-smolt survival. Detection data at LGD and throughout the hydropower systems along the Snake and Columbia Rivers allow for the estimation of parr-to-smolt survival rates. Once arriving at LGD, fish passing through the juvenile bypass are recaptured using the sort-by-code (SbyC) system in order to collect data on growth (length and weight) and condition of the fish (K). The data generated by this project provides critical information to regional fisheries managers to make informed decisions on operation of the hydropower system (FCRPS) to best aid ESA-listed fish during out-migration.1992年至2022年，美国国家海洋和大气管理局渔业部（NOAA Fisheries）在萨蒙河流域（Salmon River basin）内，为321,623尾野生幼年蛇河春季/夏季型奇努克鲑（Snake River spring/summer Chinook salmon）植入了被动集成应答器（PIT）标签，并对各野生种群的洄游时间、生长情况以及幼鲑至降海洄游幼鲑的存活率开展监测与估算工作。研究人员于夏末（7月至9月）采集鱼类样本，并在最多16个研究站点完成标记操作。当鱼类从研究站点向下格兰德水坝（Lower Granite Dam, 简称LGD）洄游时，研究团队会通过河道内的PIT检测阵列（例如瓦利溪Valley Creek阵列）以及下格兰德水坝处的监测设备收集数据，借此计算支流区段存活率、河道区段存活率、抵达时间以及幼鲑至降海洄游幼鲑存活率。在下格兰德水坝以及蛇河与哥伦比亚河沿线水电系统中获取的检测数据，可用于估算幼鲑至降海洄游幼鲑的存活率。当鱼类抵达下格兰德水坝后，通过幼鱼旁路通道的个体将借助编码分类系统（sort-by-code, 简称SbyC）进行再次捕获，以采集鱼类生长（体长与体重）及健康状况（条件因子K）相关数据。本项目生成的数据可为区域渔业管理者提供关键支撑，助力其针对联邦哥伦比亚河水电系统（FCRPS）的运行制定科学决策，以便在鱼类降海洄游期间为受《美国濒危物种法案》（ESA）保护的鲑鱼种群提供最优辅助措施。