Hierarchical Modelling Reveals Local Environmental Metrics as Key Predictors of Fish Stream Assemblage Structure Fabiane Barreto Souza, Alexandre Clistenes Alcântara Santos, André Teixeira da Silva, Nuno Caiola Ecology of Freshwater Fish, 2025 Environmental factors act at multiple spatial scales, shaping the fish assemblage structure in streams. Understanding catchment‐stream relationships through hierarchical classification can aid in the conservation and management of freshwater ecosystems. The main goal of our work was to use the Hierarchical Modelling of Species Communities framework to answer the following questions: Which environmental variables are more important in structuring stream assemblages? Do ecomorphological traits influence species' responses to environmental conditions? What is the pattern of species co‐occurrences along the streams? We fitted models with two alternative response datasets: a community matrix (site × species) with presence/absence data (PA) and abundance data (ABU). Species ecomorphological traits were also included in the models. We tested models considering the environmental variables at each scale separately (local and catchment) and considering all variables together. Variables at the local scale explained 57.1% (PA) and 53.3% (ABU) of the overall variance portion partitioning, while catchment variables explained only 36.6% and 23.3%, respectively. Traits explained only 47.9% (PA) and 18.93% (ABU) of the variation. No significant correlation between species co‐occurrences was found. Our results suggest that local‐scale metrics better predict the structure of fish assemblages in headwater streams from the Chapada Diamantina region of Caatinga.
NEOTROPICAL FRESHWATER FISHES: A dataset of occurrence and abundance of freshwater fishes in the Neotropics Lívia Helena Tonella, Renata Ruaro, Vanessa Salete Daga, Diego Azevedo Zoccal Garcia, Oscar Barroso Vitorino, et al. Ecology, 2023 The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large‐scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southern limits in Argentina, Paraguay, Chile, and Uruguay. We compiled 185,787 distribution records, with unique georeferenced coordinates, for the 4225 species, represented by occurrence and abundance data. The number of species for the most numerous orders are as follows: Characiformes (1289), Siluriformes (1384), Cichliformes (354), Cyprinodontiformes (245), and Gymnotiformes (135). The most recorded species was the characid Astyanax fasciatus (4696 records). We registered 116,802 distribution records for native species, compared to 1802 distribution records for nonnative species. The main aim of the NEOTROPICAL FRESHWATER FISHES data set was to make these occurrence and abundance data accessible for international researchers to develop ecological and macroecological studies, from local to regional scales, with focal fish species, families, or orders. We anticipate that the NEOTROPICAL FRESHWATER FISHES data set will be valuable for studies on a wide range of ecological processes, such as trophic cascades, fishery pressure, the effects of habitat loss and fragmentation, and the impacts of species invasion and climate change. There are no copyright restrictions on the data, and please cite this data paper when using the data in publications.
Diet of a bromeligenous species of treefrog in the Brazilian semiarid Silvana Souza de Oliveira, André Teixeira da Silva, Juliana Zina Brazilian Journal of Biology, 2021 Phyllodytes tuberculosus is a bromeligenous anuran species whose geographic distribution is restricted to areas of the Caatinga and to transition zones between Caatinga and Atlantic Forest in the central-south of the state of Bahia. Its existence in close relationship with bromeliads and its occurrence in dry and highly seasonal environments drove us to the supposition that species is opportunistic/generalist regard to diet. We collected the items present in the stomach of 43 P. tuberculosus individuals with stomach-flushing method. Of these, 18 stomach contents were obtained during the dry period (April–October), and 25 during the rainy period (November–March). We recorded nine classes of prey, finding the greatest relative importance for the categories Formicidae and Coleoptera in dry season and Blattodea (Termites), Formicidae and Coleoptera in the rainy season. Phyllodytes tuberculosus presented a varied, possibly opportunistic diet in semiarid environments. Additionally, we report an apparent temporal differentiation related to the typical Caatinga seasonality. This study adds to the data on the natural history of an anuran species adapted to a semiarid environment with a narrow geographic distribution.
