Guild composition and habitat use by Tetraodontiformes (Teleostei, Acanthopterygii) in a south-western Atlantic tropical estuary

Abstract

Sampling of the demersal ichthyofauna of Guanabara Bay was conducted bimonthly for 2 years at 10 stations distributed along a hydrobiological gradient. A total of 16,081 Tetraodontiformes specimens were collected, representing 10 species distributed among Ostraciidae, Monacanthidae, Tetraodontidae and Diodontidae. Tetraodontiformes appear to be well adapted to hydrological variations and inhospitable conditions prompted by intense eutrophication. However, abiotic factors traditionally considered important in estuarine community structure play a secondary role in the distribution of Tetraodontiformes. The type of sediment appears to be the most important physical factor but acts only as an indicator of ecological domain. The low explanatory power of physicochemical variables, in addition to the relative stability of the bay's ichthyofauna, suggests an influence of biological parameters. The species exhibited wide variation in their use of Guanabara Bay and utilized it as a resting, feeding and growing area. Among the species captured, Stephanolepis hispidus, Lagocephalus laevigatus, Sphoeroides greeleyi, Sphoeroides testudineus, Sphoeroides tyleri, Chilomycterus reticulatus and Chilomycterus spinosus were categorized as marine estuarine opportunists, and Aluterus heudelotii and Aluterus schoepfii were classified as marine stragglers. Acanthostracion sp. could not be categorized. The boom of C. spinosus indicates an ecological misbalance and must be carefully investigated.

Use of a species-rich and highly eutrophic tropical estuary in the South Atlantic by Pleuronectiformes (Teleostei: Acanthopterygii)

“…This diversity included species of flatfishes at different niches as indicated by different trophic levels and their distinct morphologies, which has already been indicated in other estuaries, including in Brazil (Guedes & Araújo 2008;Russo et al 2008;Lima et al 2018). The pattern observed in this study is similar to the reports for other fish groups, in which a high diversity of species was accompanied by the biomass being predominantly represented by a single species: Etropus crossotus for Pleuronectiformes, as revealed by this study, Chilomycterus spinosus for Tetraodontiformes (Andrade et al 2016), Genidens genidens for Siluriformes (Silva Jr. et al 2013), Eucinostomus argenteus for Gerreidae (Corrêa & Vianna 2016) and Micropogonias furnieri for Sciaenidae (Silva Jr. et al 2016).…”

Biodiversity, ecology, fisheries, and use and trade of Tetraodontiformes fishes reveal their socio‐ecological significance along the tropical Brazilian continental shelf

“…Tetraodontiformes trophic categories are highly diversified along the TBCS with a dominance of Omnivores (28% of the species), Zooplanktivores (24%), Invertivores (24%) and Carnivores (14%). This wide ranging feeding behaviour on multiple trophic levels provides this group an important ecological function in balancing the marine food web, influencing the structure and composition of marine ecosystems (Andrade et al, ; C.E.L. Ferreira, Floeter, Gasparini, Ferreira, & Joyeux, ).…”

“…Only a few studies have addressed the conservation, habitat, biodiversity and functional role of Tetraodontiformes fishes (e.g. Andrade, Santos, Verani, & Vianna, ; Patankar et al, ; Stump et al, ), hindering the comprehensive understanding of their importance, threats, and their complex interactions within the ecosystems.…”

Spatial distribution of juvenile fish species in nursery grounds of a tropical coastal area of the south-western Atlantic

“…Such variability may result from specialization in habitat exploitation by species and by habitat dynamics (Igulu et al 2014, Ebner et al 2016). The ability to use different environments within single ecosystems may depend on species trophic level, morphological characteristics, and functional attributes (Matthews et al 2010, Mouillot et al 2013, de Andrade et al 2015. For instance, fish which inhabit a greater variety of habitats typically present distinct physiologic adaptations, intraspecific variability in fish behaviour (Bourke et al 1997, Silva-Falcão et al 2012) and greater functional specialization and originality (Sales et al 2016).…”