Long-term variation in the ichthyofauna of Flamengo Cove, Ubatuba, São Paulo

Abstract

The Brazilian coastline extends along more than 8,000 km covering approximately 38 degrees of latitudinal range through tropical, subtropical and warm-temperate climates and includes a wide variety of marine environments such as sandy beaches, estuaries, rocky shores and reefs. This heterogeneity of habitats is reflected in the diversity of marine fishes found in Brazilian waters which sums approximately 1,300 known species. Approximately 600 marine species are estimated to occur off the coast of Sao Paulo State. Long-term studies are useful to better access variation in the fish community due to slow processes, rare or episodic events, and highly variable or complex phenomena. Our survey of the fishes of Flamengo Cove, Ubatuba, Sao Paulo, included two periods set apart 10 years from each other (1990 and 2000), in which the soft-bottom ichthyofauna was sampled with an otter trawl in autumn and spring. We sampled 782 individuals weighing 18,113.3 g representing 37 species and 19 families. Five species are considered as threatened in the State of Sao Paulo, three of them under threat of overexplotation in the federal context, and two are included in the IUCN’s Red List. The dominant family was the Sciaenidae, with eight species from both periods. We evidenced a significant variation in the structure of the ichthyofauna between 1990 and 2000, and between autumn and spring, although the number of species did not change. The most important species in terms of number of individuals and biomass were Ctenosciaena gracilicirrhus and Paralonchurus brasiliensis, respectively. Data on both of these species indicate that recruitment occurred during spring, when more and smaller individuals were sampled. More long-time studies such as this are encouraged to better understand differences in the variation of the structure of fish communities in Brazilian marine waters.