The Role of Omnivory in a Neotropical Stream: Separating Diurnal and Nocturnal Effects

Abstract

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Temporal and ontogenetic variations in feeding habits of Hollandichthys multifasciatus (Teleostei: Characidae) in coastal Atlantic rainforest streams, southern Brazil

“…In fact, most fish species use food items of allochthonous origin (Lowe-McConnell, 1999) and changes in the riparian vegetation can cause alteration in the feeding habits of freshwater fishes, affecting many links of the trophic chain (Barrela et al, 2000). Even though alterations in feeding habits can also be conditioned to ontogenetic development (Gerking, 1994), omnivory seems to be a predominant feeding strategy in small rivers in general (Pringle & Hamazaki, 1998), since food resources for fishes are mainly supplied by the forest canopy (Esteves & Aranha, 1999).…”

Ecologia e ontogenia da alimentação de Astyanax janeiroensis (Osteichthyes, Characidae) de um riacho costeiro do Sudeste do Brasil

“…A despeito das alterações morfológicas e comportamentais que acompanham o desenvolvimento, vários estudos mostraram claramente que os peixes tropicais exploram uma ampla gama de itens alimentares, mas em função da estrutura e comprimento do ducto gastrointestinal, existe um limite pré-estabelecido para a variabilidade da alimentação (e.g. Angelescu & Gneri 1949, Lowe-McConnell 1991, Pringle & Hamazaki 1998.…”

Detritivorous fish indirectly reduce insect secondary production in a tropical river

“…Tropical streams have abundant fishes, shrimps, or tadpoles that can strongly regulate production and biomass of basal resources such as algae and organic sediment (e.g., Flecker 1992a, b, Flecker 1996, Pringle and Hamazaki, 1998, Taylor et al 2006, Connelly et al 2008. By depressing benthic organic matter resources, fishes and shrimps can indirectly reduce abundances of aquatic insects (Flecker 1996, Pringle and Hamazaki 1998, Rosemond et al 1998).…”

“…By depressing benthic organic matter resources, fishes and shrimps can indirectly reduce abundances of aquatic insects (Flecker 1996, Pringle and Hamazaki 1998, Rosemond et al 1998). …”