Feeding Ecology and Trophic Interactions of Hemichromis fasciatus Peters, 1857 and Schilbe intermedius Rüppell, 1832 in a West-African Agro-Pastoral System

Abstract

Background and Aims: The diets of two small predators were characterised within a small agro-pastoral system in the savannah of northern Côte d'Ivoire. The aim was to understand feeding interactions in these systems. Study design: Qualitative and quantitative analysis of stomach contents to assess trophic interactions. Place and Duration of Study: Binguebougou agro-pastoral lake (Korhogo, Côte d'Ivoire). Sampling took place from December 2024 to November 2025. Methodology: Fish were sampled monthly. After morphometric measurements, stomachs were collected and the contents were analysed in the laboratory. The relative importance index of food (IRA) was used to quantify prey. Horn's dietary overlap index and the condition factor were used to assess the similarity of the diets of the two species and their body condition, respectively. Results: The intestinal lengths of H. fasciatus and S. intermedius suggest that both species are omnivores. The findings showed that the dietary spectrum was restricted in small agro-pastoral systems. Both species exploited the same trophic guilds. However, the prey proportions suggested that H. fasciatus is a piscivore that expands its diet to include other prey during periods of scarcity, whereas S. intermedius is a piscivore-invertivore. There was strong dietary overlap between these two species, leading to competition within the Binguebougou agro-pastoral system. Although the condition factor did not reveal any significant impact on either species, H. fasciatus appears to be in a more favourable position, with higher condition factor values. Conclusion: In the Binguebougou agro-pastoral system, the diets of these two species were very similar, putting them in competition for access to food sources. However, this competition had not yet affected the well-being of H. fasciatus and S. intermedius in this environment.