Influência da vazão e da precipitação na avaliação do estoque de piramutaba Brachyplatystoma vaillantii da costa norte do Brasil

Abstract

The fish production in the region of the north coast is developed according to the Amazon river and its supply of nutrients discharged by the large volume of fresh water, resulting in especially high productivity of fish resources in the region, including the piramutaba Brachyplatystoma vaillantii, catfish target of this study and of great economic importance. The variation of displacement of this species is closely related to their migratory behavior, fluctuations in water levei, flow of the Amazon River, and the displacement of the contact zone between fresh and marine waters in the estuary because seasonality is presented as a factor determinant of fish production in the region. And the management of fisheries resources is necessary both for the conservation of Amazonian aquatic systems and the maintenance of an activity of outstanding socio-economic importance for the Amazonian traditional population. Compreend the relationship between the distribuition of the fishing resources and the enviroment factors contributes to a racionalist and tenable stocks. From this assumption analyse the relationship between preciptation and river flow that flow into north coast upon CPUE fishing of piramutaba catfish B. vaillantii trought the software CLIMPROD to the application of a model of excedent production with the incorporation of the enviroment variables. To this end, were used data above the monthly landed average production (t) and fishing effort (sea days) obtained by the files of monthly control of landing of industrial fishing to a period from 1995 to 2007 available by the project Estatatpesca IBAMA/UFRA; data flows considering the sum of the daily averages for each year of study in m3/s, and precipitation, their average monthly totais (mm), both available on the website of the Agência Nacional de Águas - ANA.