Influência do ciclo hidrológico em pescarias comerciais na Amazônia Central, Brasil

Abstract

In the Central Amazon, the fisheries are artisanal in character, being practiced by fishermen in rivers and flooded areas. Thus, the main issue addressed in the study is to verify how the hydrological cycle influences the catches of species, considering that the landing is made up of species with different feeding strategies. Firstly, we carried out a previous characterization of the fisheries, in order to determine the main environments and species exploited, as well as, more productive and attractive periods for the fishing activity. We also list the fishing gear used by fishermen with the target species. The characterization indicated that the lake environments are more exploited by the fishermen, however, most of the catches come from the river channels. In relation to the composition of the landing, a total of 34 species were landed, being the jaraqui coarse scale (Semaprochilodus taenirus) and the jaraqui fine scale (Semaprochilodus insignis) the most exploited species. The period of flood presented a significant difference in the catch values per unit of effort (CPUE) when compared to the other hydrological periods. The fishing gear varied according to the environment where the fishing occurred and the species to be exploited. Later, we used generalized linear models (Covariance Analysis - ANCOVA) to determine the influence of the river level on the fisheries in the Lower Solimões River. The analysis of covariance for the flood period showed that all species were influenced by river level, and by fishing effort, there was still a positive interaction between fishing effort and detritus species. During the flood period, the fishing effort positively influenced all species, there was also a positive interaction between fishing effort, detritivorous and herbivorous species and a positive effort in river environments. In the ebb period, only the fishing effort was significant, with a negative interaction between the fishing environment and the effort. In the dry season, only the omnivorous species were influenced by the fishing effort and the level of the river, with negative interaction between fishing effort and omnivorous species. The results found may contribute to the generation of knowledge about fishing activities, providing information for the construction of public policies related to fisheries management in the state of Amazonas.