Rivers Trust Salmonid Grades 2022 to 2024

These data are the final result of electrofishing surveys conducted by Westcountry, West Cumbria, Ribble and South Cumbria Rivers Trusts between 2022 and 2024. The cut off length between fry and parr was estimated using expert judgement. This was used to estimate the fry count per survey. These data are formatted in long format with only one grade attribute and one count attribute. Filtering is performed using the species attribute. To download these data and raw electrofishing results see https://monitoringhub.catchmentbasedapproach.org/pages/getdata [1] Zippin, C. 1956. An evaluation of the removal method of estimating animal populations. Biometrics 12:163– 169. 9本数据集为2022至2024年间由韦斯特康特里（Westcountry）、西坎布里亚（West Cumbria）、里布尔（Ribble）及南坎布里亚河流信托（South Cumbria Rivers Trusts）开展的电鱼调查最终成果。幼鱼（fry）与稚鱼（parr）的分界体长通过专家经验判定，以此估算每次调查的幼鱼数量。本数据集采用长格式（long format）存储，仅包含1个等级属性与1个计数属性，可通过物种属性执行数据筛选。如需下载本数据集及原始电鱼调查结果，请访问：https://monitoringhub.catchmentbasedapproach.org/pages/getdata [1]。 [1] 齐平（Zippin, C.），1956年。《动物种群数量估算移除法的评估》（An evaluation of the removal method of estimating animal populations）. 《生物统计学（Biometrics）》12:163–169. 9