Assessing fish stocks harvested by small-scale fisheries is challenging. The lack of official fisheries data constrains the proper management of such fisheries. Thus, alternative sources of information are crucial to enrich data-poor fisheries. Here, we evaluated different sources of data for the mullet (Mugil liza) fishery, one of the most important but overexploited fisheries in Brazil. We gathered three alternative sources of catch data by artisanal fisheries: 14 years of self-reported catches by artisanal fishers across 24 municipalities; 16 years of catches by traditional beach seines mined from news outlets; and 13 years from a single community monitoring their beach seine catches. We tested whether alternative data sources follow the same trends of landing reports from systematic, official monitoring of the industrial fleet. We fitted Bayesian time-series models to test if environmental changes and stock abundance can predict these data. We found that only self-reported catches matched the official reporting trends, thereby improving our understanding of changes in the mullet stock. These findings reveal that self-reported catches by fishers provide reliable additional data useful for management. Self-reporting data are cost-effective, deals with the complexity of small-scale fisheries, and welcomes fishers as key stakeholders in management practices.

中文翻译：

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替代数据源可以填补数据匮乏渔业的空白

评估小规模渔业捕捞的鱼类资源具有挑战性。官方渔业数据的缺乏限制了对此类渔业的适当管理。因此，替代信息来源对于丰富数据匮乏的渔业至关重要。在这里，我们评估了鲻鱼 (Mugil liza) 渔业的不同数据来源，这是巴西最重要但过度开发的渔业之一。我们收集了手工渔业捕捞数据的三个替代来源： 24 个城市的手工渔民 14 年自我报告的产量；从新闻媒体开采的传统海滩围网 16 年的渔获量；和 13 年从一个社区监测他们的海滩围网渔获量。我们测试了替代数据源是否遵循对工业船队进行系统、官方监测的着陆报告的相同趋势。我们拟合了贝叶斯时间序列模型来测试环境变化和种群丰度是否可以预测这些数据。我们发现只有自我报告的渔获量与官方报告趋势相符，从而提高了我们对鲻鱼种群变化的理解。这些发现表明，渔民自我报告的渔获量为管理提供了可靠的额外数据。自我报告数据具有成本效益，处理小规模渔业的复杂性，并欢迎渔民成为管理实践的关键利益相关者。这些发现表明，渔民自我报告的渔获量为管理提供了可靠的额外数据。自我报告数据具有成本效益，处理小规模渔业的复杂性，并欢迎渔民成为管理实践的关键利益相关者。这些发现表明，渔民自我报告的渔获量为管理提供了可靠的额外数据。自我报告数据具有成本效益，处理小规模渔业的复杂性，并欢迎渔民成为管理实践的关键利益相关者。