Subtle trophic differentiation and seasonal reorganization among sympatric pipistrelle-like bats in West African rice agroecosystems

Abstract Trophic differentiation among sympatric species is often treated as relatively stable, yet seasonal changes in resources may reorganize how species share their trophic niche. We examined whether trophic relationships among three sympatric pipistrelle-like bats, Afronycteris nanus, Neoromicia somalicus , and Pseudoromicia rendalli , were persistent or changed through time in West African rice agroecosystems. Using DNA metabarcoding of faecal samples from 78 individuals, we identified 244 prey OTUs spanning 13 arthropod orders. Diets were broad and consistent with generalist insectivory, with Blattodea, Hemiptera, and Coleoptera contributing most across species. Despite this similarity, OTU-level dietary composition differed significantly among species, although species identity explained only a small proportion of variation. Dietary overlap was moderate (Pianka = 0.491–0.602) and higher than expected under a null model. Temporal variation was stronger than interspecific differentiation. Diets in June (early wet season) and December (dry season) were strongly differentiated, and interspecific overlap shifted from high in June (0.543–0.642) to lower in December (0.095–0.173), while within-species overlap between periods was near zero. Seasonal change did not simply strengthen or weaken a fixed pattern of trophic segregation: the configuration of dietary similarity was reorganized through time, as species pairs differing significantly in dietary composition changed between June and December. Temporal changes in major prey orders were largely shared among species, with little evidence for consistently divergent species-specific trajectories. Together, these results show that trophic differentiation among these morphologically similar bats is modest overall, but temporal variation can reorganize the configuration of trophic similarity among species.