Food resources sustaining the fish fauna in a section of the upper São Francisco River in Três Marias, MG, Brazil (original) (raw)
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Acta Limnologica Brasiliensia, 2018
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Neotropical Ichthyology
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Food resources used by three species of fish in the semi-arid region of Brazil
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Neotropical Ichthyology, 2009
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Acta Scientiarum. Biological Sciences, 2016
We described the spatial distribution of fish trophic groups in the Água Boa Stream, MS, Brazil. Specimens were caught using electrofishing in the upper, intermediate and lower stretches of the stream, between March and November 2008. We analyzed 415 stomach contents of 24 species. Detritus/sediment and aquatic invertebrates were the main exploited resources. Ordination analysis categorized the species in six trophic groups. Aquatic invertivores showed the highest richness (10 species), followed by detritivores (08 species), omnivores (03 species), terrestrial invertivores (03 species), algivores (02 species) and herbivore (01 species). Three trophic groups occurred in the upper stretch, six in the intermediate and five in the lower. Detritivores, omnivores and algivores showed the highest density, while detritivores and aquatic invertivores presented the highest biomass. Autochthonous resources were particularly important to the studied fish fauna, especially aquatic invertebrates, so, conservation actions reducing the simplification of the habitat by silting and recovering the riparian forest are essential to maintain the ichthyofauna of the Água Boa Stream.
Environmental Biology of Fishes, 2004
We evaluated fish assemblage diet and trophic structure in five lakes (Patos, Zé do Paco, Fechada, Ressaco do Pau Véio and das Garças), connected or not with the river. Trophic structure analysis was based on the species whose number of sampled digestive tracts was greater or equal to 10 and ordinated according to a detrended correspondence analysis. We identified seven trophic guilds with the following representatives: (1) Detritivorous–ileophagous: Cyphocharax modestus, Prochilodus lineatus, Steindachnerina insculpta and Loricariichthys platymetopon; (2) Herbivorous: Schizodon borellii and Leporinus lacustris; (3) Benthophagous: Iheringichthys labrosus, Satanoperca pappaterra and Trachydoras paraguayensis; (4) Insectivorous: Astyanax altiparanae, Moenkhausia intermedia and Parauchenipterus galeatus; (5) Piscivorous: Hoplias cf. malabaricus and Serrasalmus marginatus; (6) Carnivorous–carcinophagous: Pimelodus maculatus and (7) Insectivorous–lepidophagous: Roeboides paranensis. The detritivorous–ileophagous guild was the predominant one in the five lakes.
Diet and trophic organization of the fish assemblage from the Mamanguape River Estuary, Brazil
Latin American Journal of Aquatic Research
The present work aims to characterize a fish assemblage from a northeastern Brazilian estuary according to its diet and trophic organization along the estuarine-reef gradient. Sampling was performed at the Mamanguape Estuary, and fishes were collected using three types of nets at seventeen sites, grouped into four regions according to salinity range: reefs and the lower, middle, and upper estuary. The most abundant species were Atherinella brasiliensis, Mugil curema, and Sphoeroides testudineus. The highest species abundance and richness was observed for the lower estuary. Zooplankton was the most consumed category, recorded for fortytwo species. Among the guilds, piscivores were the most abundant, followed by crab eaters. Herbivores, mostly represented by Abudefduf saxatilis, had a higher abundance in reefs, being correlated according to ANOSIM analysis to this region, while piscivores and crab eaters showed a high contribution to inner regions of the Mamanguape Estuary.
Environmental Biology of Fishes, 2001
As part of a larger project that aimed to determine the factors that regulate fish productivity in a clear water river of the Atlantic rainforest, São Paulo State, Brazil, composition and the trophic structure of the fish community of the middle course of the river were studied from January 1995 to May 1996. Of the 17 species collected, Mimagoniates microlepis, Schizolecis guentheri, Phalloceros caudimaculatus and Kronichthys heylandi accounted for 83.2% of the total fish abundance. Most of the species were insectivorous (35.7%), followed by detritivores (21.4%), benthivores (14.2%), omnivores (14.2%), herbivores (7.1%), and piscivores (7.1%). Results of food overlap analysis as calculated by the Index of Morisita showed that 17.5% of the species pairs overlapped. Habitat segregation, however was observed among most of the species, suggesting some degree of food partitioning. Despite the characteristics of this escarpment river, which produces spates year round, no seasonal variation in diet was observed, suggesting that although food abundance may fluctuate throughout the year, most items are in constant supply. The importance of allochthonous food was considered and it appears that, though only a few species feed on this source (including detritivores), they make up 87.2% of the total fish abundance. The low abundance of most of the fishes, the high number of endemic species and the strong dependence of the species on a few food resources suggest that these systems are sensitive to anthropogenic impacts and require future studies. 1 Buckup, P.A. 1998. Biodiversidade dos peixes da Mata Atlântica. pp. 1-9. In: Base de Dados Tropical (ed.) Biodiversity Angermeier & Karr (1983) suggest that large scale alterations in forest structure may have serious impacts on stream biodiversity, affecting effects of shading, discharge variability, siltation and available food types. Although some studies on fish communities of clear water streams of the Atlantic rainforest describe community composition and main food habits of species (Sabino & Castro 1990, Uieda 1995, Buck 2000), several aspects of the ecology of these communities still remain unknown. As the escarpment clear water river here studied is subject to unusual conditions as spates throughout the year, which may provide changes patterns of South and Southeast Atlantic Rainforest.
Biodiversidade, 2014
The aim of this study was to evaluate the trophic ecology of the principal species of fish (Astyanax altiparanae, A. fasciatus, Bryconamericus stramineus, B. iheringii, Cheirodon stenodon, Characidium fasciatum, Geophagus brasiliensis, Hyphessobrycon anisitsi, Piabina argentea and Steindachnerina insculpta) captured in the littoral region of the Rio dos Veados (23º16'80''S/48º38'67''W), an affluent of the Rio Paranapanema, SP. The collections were conducted monthly with a seine-type trawling net with a 5.0mm mesh size, taking place between August, 1996 and December, 1997. This collection time was subdivided into the dry (April to September) and rainy (October to March) seasons. The food contents were analyzed by a volumetric method, and the food overlap determined by the Morisita-Horn index. The ten species of fish consumed different food resources, which varied in abundance (volume percentage): detritus/sediment (30.0%), aquatic insects (23.4%), microcrustaceans (17.6%), terrestrial insects (13.9%), higher plants (6.2%), algae (5.6%), fish (1.8%), and macroinvertebrates and microinvertebrates grouped together (1.5%). Patterns of similarity among the species were constructed utilizing Detrended Correspondence Analysis (DCA) with removal of the arch effect and tested by analysis of variance (unifactorial ANOVA), showing that there was no significant variation in the composition of food resources utilized by the species during the dry and rainy seasons. The main resources consumed by the ten species were classified into three trophic categories: omnivores, detritivores and insectivores. Interspecies food overlap revealed indices of 0.059 to 0.961, showing it to be independent of the period studied, since the resources utilized were similar, both in qualitative and quantitative terms. Intraspecies food overlap in the different periods was minimal for A. altiparanae (0.662) and maximal for S. insculpta (1.0). The species studied showed little variation in relative length of intestine, with the exception of S. insculpta which had an elevated intestinal index. The variations in food resources utilized between the periods were of little relevance, indicating that the temporal factor did not influence the resources utilized by the species studied. Of the ten species studied, nine could be viewed as generalists, considering the food resources utilized during the two periods, and only S. insculpta behaved as a specialist.