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bioRxiv · 10.1101/2025.10.20.683447

Application of CMSY method to estimate biological reference points of Piracatinga (Calophysus macropterus Lichtenstein, 1819) from the upper Solimoes River in the Amazon Basin

Perez Lozano, A.·Taphorn, D. C.
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Abstract

The Amazon basin contains a wide variety of commercially valuable fish species, with fishing being the main source of income for artisanal fishermen and riverside communities. After the decline in large catfish production in the late 1990s, Piracatinga emerged as an alternative to the local economy and was intensively exploited between 1996 and 2012. However, its capture became uncontrolled and was finally banned in 2015. Despite this, an assessment has never been conducted. The objective of this study was to determine Biological Reference Points (BRP) to estimate the level of exploitation. For this purpose, the (CMSY) assessment method was applied, using fishing statistics. The results showed that Piracatinga is in a sustainable situation. The biomass indicators for optimal sustainable yield (BMSY = 2.25 t) and fishing mortality (F) values at the maximum sustainable yield point (FMSY = 0.55). Therefore, the population status of the Piracatinga stock is in "good condition" (F2012/FMSY (<1) and B2012/BMSY (>1). These results indicate that despite the good condition of the resource, we recommend precautionary measures of a technical and legal nature before allowing its exploitation again.

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Perez Lozano, A., Taphorn, D. C.. 2025-10-21. Application of CMSY method to estimate biological reference points of Piracatinga (Calophysus macropterus Lichtenstein, 1819) from the upper Solimoes River in the Amazon Basin. https://doi.org/10.1101/2025.10.20.683447

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