Estrutura de uma assembleia de peixes em um ambiente marinho-estuarino no litoral de Pernambuco

Abstract

Estuarine environments, as well as surf zones, despite being highly important both ecologically and economically, have been facing various anthropogenic pressures over time, which can be observed in aquatic communities, such as fish fauna. Thus, this study aimed to analyze the fish community structure in a marine-estuarine environment in Maracaípe throughout the year. Collections were conducted monthly between August 2020 and July 2021, during daytime ebb tide of the new moon, in the estuary and surf zone north of the river mouth. Daytime replicates of beach seine netting were performed. Abiotic data of salinity and temperature were measured at each sampling point, and collected individuals were measured and weighed in the laboratory. Ecological indices including species richness, Shannon-Wiener diversity, Pielou's evenness, dominance, total and relative abundance were analyzed. Cluster analysis was conducted using the Bray-Curtis similarity index based on abundance and presence-absence matrices of species. Non-metric multidimensional scaling (nMDS) and canonical correspondence analysis (CCA) were also performed to confirm the data patterns. Chi-square test between collection points and months, as well as ANOSIM test, were conducted to determine the significance of the data. Data analyses and graphs were performed using PAST and Excel software. A total of 13,614 individuals, 29 families, and 66 species were identified. Clupeidae, Engraulidae, and Haemulidae were the most abundant families. Lile piquitinga (38%) and Haemulopsis corvinaeformis (17.09%) were the most abundant species. In March, there was a high dominance of H. corvinaeformis in the surf zone, while in October, dominance was observed for L. piquitinga in the estuary. Overall, the surf zone exhibited higher diversity indices (2.22) and richness (47) compared to the estuary. There was also species segregation regarding habitat use: Atherinella brasiliensis, Lile piquitinga, and Eucinostomus argenteus were predominantly estuarine species, while Haemulopsis corvinaeformis, Larimus breviceps, and Polydactylus oligodon were typical species of the surf zone. These findings highlight the importance and necessity of management actions for the sustainable use of coastal regions, given their significant ecological and economic value.