Patterns of fish and crustacean community structure in a coastal lagoon system, Rio de Janeiro, Brazil

Abstract

Coastal lagoons are feeding and nursery habitats for fish and crustaceans and fishing grounds for some of these species. This work describes the fish and crustacean community structure of the Piratininga–Itaipu lagoon system (Niterói, Rio de Janeiro, Brazil), evaluating the importance of environmental factors in structuring spatial and temporal changes. Sampling was conducted using gill-nets, cast-nets, hoop-nets and fish traps during summer and winter of 2006. A total of 50 fish and 9 crustacean species were collected, amounting to 17,143 specimens. Few species dominated in abundance, frequency and biomass. The marine–estuarine species Atherinella brasiliensis and Cetengraulis edentulus were most abundant in Piratininga and Itaipu, respectively. Analysis of Similarity, nMDS and Canonical Correspondence Analysis indicated a strong spacial segregation between Piratininga and Itaipu and to a lesser extent a seasonal component. Salinity was the main factor influencing species distribution, followed by water depth, water temperature and, to a lesser extent, organic matter in the sediment and bottom vegetation. A large number of occasional species occurring at sampling sites near the Itaipu channel, which connects the lagoon to the sea, suggests a high degree of communication between this lagoon and the adjacent marine coastal environment, unlike Piratininga lagoon, which has an indirect communication with the sea.