Catch‐per‐unit‐effort is often used as an approximation of population size. However, for the management and conservation of populations, information about the number of individuals is fundamental. Pike, Esox lucius L., is a popular fish species for recreational anglers. In this study, data in the form of journal keeping by anglers were used: date; place; and photographs of the captured fish; pike were identified based on their natural markings in combination with length measurements. The data were analysed by spatial capture–recapture (SCR) models. Results showed that a small and densely vegetated lake (6.7 ha) in south‐eastern Sweden had a population size of 91 (±22 SE) pike ≥60 cm. On one occasion, 10 individuals were caught, that is 11.1% of the population, highlighting that angling may potentially have a substantial impact on the population size. Hopefully, this study can inspire angler–manager collaborations for conservation of fish stocks.

中文翻译：

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作为公民科学家的休闲垂钓者可以提供数据来估计梭鱼的种群规模，Esox lucius

每单位努力的渔获量通常用作种群规模的近似值。然而，对于种群的管理和保护，关于个体数量的信息是至关重要的。派克，Esox lucius L.，是一种深受休闲垂钓者欢迎的鱼类。在这项研究中，使用垂钓者记日记形式的数据：日期；地方; 和捕获的鱼的照片；梭鱼是根据其自然标记结合长度测量来识别的。数据通过空间捕获-再捕获（SCR）模型进行分析。结果表明，瑞典东南部一个植被茂密的小湖（6.7 公顷）的种群规模为 91 (±22 SE) 条≥60 厘米的梭鱼。有一次，抓到了 10 个人，占人口的 11.1%，强调钓鱼可能会对种群规模产生重大影响。希望这项研究可以激发垂钓者与管理者在鱼类种群保护方面的合作。