Decifrando os desembarques de grandes bagres migradores: Como as características operacionais e sazonais moldam a pesca no estuário Amazônico?

Abstract

Fishery resources play an important role in the global economy. In the Amazon, fishing is a traditional and economically significant activity that provides both income and food security. Amazonian fish production is dominated by large migratory catfish species, such as piramutaba, dourada, and filhote, which depend on extensive migrations to complete their life cycle. Analyzing fishery activity data is an indirect approach to assessing fish populations. This study aimed to investigate the operational, spatial, and temporal characteristics that influence the occurrence and intensity of catches of B. rousseauxii, B. vaillantii, and B. filamentosum at the mouth of the Amazon River. Using advanced statistical tools, we evaluated the relationship between the CPUE of B. rousseauxii, B. vaillantii, and B. filamentosum as a function of seasonality and fishery operational characteristics, such as fishing area and vessel fishing power in the Amazon estuary. To account for zero-inflated data, a Hurdle model was applied, allowing a two-part structure: a binary component indicating the absence of CPUE and a continuous component modeling positive CPUE values. The CPUE of dourada is influenced by vessel classification and by the interaction between area and period. The CPUE of piramutaba varies with fishing area and period, and the effect of the period changes depending on the area. The CPUE of filhote varies with vessel type, area, and period, and the effect of the period also changes according to the area. These findings underscore the need for management strategies that incorporate the seasonality and spatial heterogeneity of fishing in the Amazon estuary.