Evaluation of an Artisanal Freshwater Fishery in Guatemala Finds Underfished Conditions

The assessment of the stock status of inland artisanal fisheries is extremely difficult due to limited or absent historical data on catch, effort, or recruitment. Most of these fisheries are considered potentially overfished due to their open-access nature and poor management. Alternately, fishing below maximum yield could cause a loss in potential yield as well as food supply for local communities. The Giant Cichlid Petenia splendida has been considered to be overexploited in Guatemala. Our objective was to measure fishing mortality using a passive tagging study with reward tags for the Giant Cichlid fishery in Lake Peten Itza to explore the potential for overfishing. In total, 24% of the tags were returned, and the return rate increased with the value of the reward (similar to US$6, $12, $18, and $25). We explored two reporting rate scenarios. Exploitation rate was estimated as 0.36 when the reporting rate was 100% and 0.48 when the reporting rate was 75%. A sensitivity analysis for yield-per-recruit and spawning potential ratio models indicated that this fishery was below the maximum sustainable yield without recruitment overfishing risk under both scenarios; thus, more stringent regulations are not required at this time. Moreover, under a conservative scenario, exploitation rates could increase yield by up to 40% for fish over 240 mm, suggesting the potential for increased resource utilization without causing growth or recruitment overfishing, and should not exceed 60% with fish under 220 mm TL. This study provides a preliminary assessment of the size limit and harvest rate that can prevent overfishing of the Giant Cichlid. Similar tag reward methods can be effectively applied to assess artisanal fisheries. The underfished condition in this fishery demonstrates that open-access fisheries are not always overexploited, and there is a need for a better understanding of local regulations' effectiveness and the role of social and economic factors influencing artisanal fisher behavior.

Automated summary

Assessing the stock status of inland artisanal fisheries is challenging due to limited historical data, but it is important to avoid overfishing. This study used passive tagging with reward tags to measure fishing mortality of Giant Cichlid fishery in Guatemala, revealing that the fishery is currently below maximum sustainable yield without the need for stricter regulations.