Trophic relationships with Penaeoidea shrimp and bycatch fauna explored by fishery of Ubatuba littoral, São Paulo

Abstract

Trawling is one of the most important commercial activities that exist in the Ubatuba region, and it has target species like pink shrimp (Farfantepenaeus brasiliensis and F. paulensis) and sea-bob shrimp (X. kroyeri). This type of fishing is random, and besides the target species, it is collected a bycatch fauna which they have lower or null economic value. In this way, with the crescent concern of the possible impacts that this type of fishing can cause in the benthic environment and this hard exploration caused environment degradation in those animals invertebrates and vertebrates habitats, where they achieve their life cycle. Thereby, the present project objective is to identify the possible target species of the region and to understand how the trophic webs are structured. The method used in this project is the stable isotope, and with them it is able get information about trophic level and the trophic relations presented in the ecosystem. The isotopic analyzes will be made with ´13C e ´15N and the package SIAR (software R) will be used in the identification of level trophic and in the trophic web of the collected species in the trawling. (AU)