Avaliação ambiental e estrutura das comunidades de peixes e invertebrados marinhos em áreas de arrasto camaroeiro do litoral de Santa Catarina, Brasil

Abstract

The shrimp trawling is carried out all over the Brazilian coast and has a significant economic, social and cultural importance. This type of fishing is recognized by the impacts that they cause on the substrate and benthic fauna, being effective for the target species, but not selective for the others species, considering that most of them are caught "unintentionally". In this work, the trawls of three traditional fishing areas of the Santa Catarina coast were analyzed from different perspectives, leading to the elaboration of four chapters. The first chapter deals with the environmental and ecological evaluation of the invertebrate species that occur in these places, the relationships with the environmental variables and possible impacts in the trawling areas. In the second chapter, under the same perspective of the first, the ichthyofauna of these sites was analyzed to evaluate its response to environmental conditions. The third chapter presents a conservationist approach, where the fish and invertebrate communities were evaluated in order to identify the best strategy for conservation, considering the dissimilarities and the organization of the species among the sites. Finally, the fourth chapter provides biological information on the main fish species from the central locality of our studies (Penha-SC). Considering the three studies, we conclude that: (1) - the areas are under frequent disturbances; (2) - Barra do Sul has a homogeneous substrate, predominantly sandy, which causes negative effects in the fish and invertebrates communities, (3) - Porto Belo has the highest diversity of species and the best quality of habitats, while Penha is in an intermediate situation between the studied environments; and (4) - three environments are different and have a high conservation value, particularly for high turnover of species. Therefore, these areas need prioritization for regional conservation. Stimulating future bycatch experiences for biota knowledge is necessary, since most of the marine invertebrate and fish species captured in this study lack behavioral, biological, and ecological information. Thus, to know more about the dynamics of the populations affected in this and in the other trawling areas of the Brazilian coast is of extreme importance to manage and contribute with the conservation of the species, aiming the sustainability of the fisheries.