Impactos das mudanças climáticas sobre comunidades pesqueiras em decorrência da redistribuição do pescado na Bacia Amazônica.

Abstract

The impacts of climate change affect both natural ecosystems and human populations that depend on the ecosystem services they provide, establishing a link between ecological transformations and social consequences. In the case of the Amazon Basin, riverine populations rely on fishing as their main source of food and livelihood, making food security directly tied to the availability and distribution of fishery resources. In this context, this study aimed to assess the impacts of climate change on the distribution of fish species important for commercial fishing in the Amazon Basin and to analyze the displacement needs of human populations dependent on this resource for fishing in refuge areas for fish stocks. To this end, Ecological Niche Models (ENMs) were used to project changes in the distribution of 15 species relevant to fisheries under two carbon emission scenarios (SSP2-4.5, moderate, and SSP5-8.5, pessimistic) for the years 2050 and 2090. Additionally, circuit analysis was applied to estimate the potential for human displacement from the main landing sites in the basin toward the identified climate refugia, considering the cost of access to fish under different future conditions. The results show that the distribution patterns of commercially important fish species are expected to experience significant reductions by the end of the century, especially under more pessimistic carbon emission scenarios. Species such as Prochilodus nigricans and Plagioscion squamosissimus are projected to retain broad climatically suitable areas in the future, while most species are expected to experience large losses in their distribution ranges. Climate-environmental refugia for the species are projected to be highly fragmented areas, mainly concentrated in the western portion of the basin. Projections indicate that fishing communities along the Amazon, Madeira, and Purus rivers may face declining fish availability and the need to migrate - either temporarily or permanently - in search of areas with greater fish abundance, particularly toward the western region of the basin. The findings of this study can help guide climate adaptation policies that take into account the realities of populations dependent on fishing in the face of ongoing climate change.