ANÁLISES BIOMORFOMÉTRICAS DE PEIXES DA MICROBACIA DO RIO PRAQUIQUARA, MÉDIO APEÚ, AMAZÔNIA ORIENTAL

Understanding how aquatic organisms behave in their natural habitat is an essential activity and one of the techniques that contribute to this understanding is morphometry, which studies the relationship between shape and body growth of fish. With this, this work aims to analyze the morphometric characteristics for two species of fish being, Bryconops giacopinii and Geophagus proximus, in order to support future studies on the dynamics of growth of these species in the Praquiquara river microbasin. The collection of biological material took place between July 2017 and June 2018, from the access to Fazenda Escola de Castanhal - UFRA, using a 2 m throw net with a 1.5cm mesh and gill nets of 15, 25 and 30m in length and 1.6 m high, the caugth fish were identified, measured and weighed in terms of morphometric characters, then the data were processed from a linear regression and the weight-length data were logarithmized to adjust the regression. The data were analyzed using the R software. The results showed that the variables presented correlation that were within the scale of moderate to strong positive (r > 0.50) for both species and that the allometry (b = 3) for the relationships were negative, with the exception of the weight-length relationship of the G. proximus species that presented an isometric growth. Therefore, the microbasin can comprise the feeding area for the studied species, as well as the area of refuge and protection.