Ontogenetic diet shifts in a neotropical catfish, Sorubim lima (Schneider) from the River Paraná System
Abstract:This study examines the diet of Sorubim lima (Schneider) during its early life stages and compares it with available food resources. Prey species preference was estimated by computing the Strauss index. The diet was diverse, and rotifers and cladocerans were the most important items. Pre-flexion larvae ate rotifers and cladocerans. Around flexion, cladocerans were dominant and the ingestion of fish also began. As larvae grew, the percentage of rotifers diminished. In post-flexion larvae, cladocerans were also dominant, and the ingestion of insects and fish was more frequent. The Strauss index showed negative selection for rotifers, positive values for cladocerans and neutral for copepods. The role of the lotic habitats as nursery areas for fish larvae was discussed.
Document Type: Research Article
Affiliations: Instituto Nacional del Limnología (INALI-CONICET), Santo Tomé (Sta.Fe), Argentina
Publication date: April 1, 2001