Afognak Lake sockeye salmon stock monitoring project (2017–2019)

The Afognak River (Litnik) has historically supported one of the largest sockeye salmon subsistence fisheries for Kodiak Archipelago residents. In the 2000s, the number of sockeye salmon returning to Afognak River had diminished substantially resulting in closures to commercial, sport, and subsistence fishing in Afognak Bay. Local subsistence users, represented by the Kodiak-Aleutians Regional Advisory Council, Kodiak Fish and Game Advisory Committee, and Kodiak Tribal Council, stressed the importance of the Afognak River system to local subsistence users and contended that continued closures would make it more difficult for local residents to meet their sockeye salmon needs and shift fishing efforts to small nearby sockeye salmon runs. The Afognak Lake Sockeye Salmon Stock Monitoring Project enumerates adult sockeye salmon into Afognak Lake through a weir located on the Afognak River, describes run-timing, or proportional daily passage, of sockeye salmon through the weir, estimates the..., Weir Installation and Adult Salmon Enumeration

A 27 m long weir was installed perpendicular to the stream flow and consisted of 10 wooden tripods (each tripod consisting of three 4″ x 4″ x 8′ spruce timbers and 2″ x 6″ x 6′ horizontal cat-walk supports), 33 aluminum pipes (2″ x 10′), 44 picketed aluminum panels (1″ aluminum pipe with 1″ spacing totaling 30″ x 6′), and 2 framed panel gates. All materials were secured with sand bags and lashed together to create a fish tight structure that conformed to the contour of the stream channel.

Two counting gates were placed between panels in the two deepest channels of the river enabling fish to be counted as they pass through the weir. A white flash panel was placed on the substrate beneath each gate to enhance visibility and species identification. Fish were counted by field technicians using hand tally denominators as fish migrated upstream through the gates. The counting gates remained closed until staff were present to count fish thro..., RUHL_DATASET_readme.txt file

Escapement Data.csv - Daily and cumulative escapement through the weir by day
ASL Data.csv - Age Sex Length data by week

阿福格纳克河（Litnik，Afognak River (Litnik)）历史上是科迪亚克群岛居民开展红鲑（sockeye salmon）传统生计渔业的核心水域之一。21世纪初，洄游至阿福格纳克河的红鲑种群数量大幅下滑，导致阿福格纳克湾的商业、休闲及生计渔业全面关停。由科迪亚克-阿留申地区咨询委员会、科迪亚克渔业与野生动植物咨询委员会以及科迪亚克部落议会代表的当地生计渔业从业者，多次强调阿福格纳克河水域系统对本地居民生计的关键意义，并指出持续关停渔业将令当地居民更难满足红鲑消费需求，进而迫使捕捞活动转向附近小型红鲑洄游种群。

阿福格纳克湖红鲑种群监测项目（Afognak Lake Sockeye Salmon Stock Monitoring Project）通过架设于阿福格纳克河的测鱼堰（weir）统计洄游进入阿福格纳克湖的成年红鲑数量，记录红鲑的洄游时序或单日通过占比，并开展相关估算……【测鱼堰架设与成鱼计数】

27米长的测鱼堰垂直于水流方向架设，由10座木质三脚架（每座由3根4英寸×4英寸×8英尺的云杉木料，搭配2英寸×6英寸×6英尺的横向人行过道支撑构件组成）、33根2英寸×10英尺的铝制管材、44块带栅格的铝制面板（采用间距1英寸的1英寸铝制管材制作，单块尺寸为30英寸×6英尺）以及2扇框架式闸门组成。所有构件均以沙袋固定并绑扎紧实，搭建出贴合河道轮廓的密闭拦鱼结构。

两道计数闸门分别设置在河道两处最深航段的面板之间，使鱼类通过堰体时可被逐一计数。每道闸门下方的河床基底均铺设白色反光面板，以提升可视度并辅助物种识别。野外技术人员通过手动计数器，对溯河洄游通过闸门的鱼类进行计数。计数闸门仅在工作人员到场开展鱼类计数作业时保持开启……

本数据集包含RUHL_DATASET_readme.txt说明文件，以及以下两个数据文件：
1. Escapement Data.csv：按日统计的测鱼堰过坝红鲑洄游数量及累计总量
2. ASL Data.csv：按周统计的年龄-性别-体长（Age Sex Length，缩写ASL）数据