Feeding Patterns and Strategies of Ephemeroptera, Plecoptera and Trichoptera in Relation to Seasonality, Landscape Elements and Mesohabitats

Abstract

We inspected functional feeding groups in relationship with seasonality, stream order, Land Scape Elements (LSE), and mesohabitat of Ephemeroptera, Plecoptera, and Trichoptera (EPT) based on gut content analysis and mouthparts in 27 streams of the Western Ghats and the Eastern Ghats. From the study, a total of 14,168 specimens were collected and identified. The composition of trophic categories showed a slight variation among the different seasons with the dominance of collectors. The results of the abundance of functional feeding groups of EPT across stream orders additionally showed the predominance of collectors and predators in-stream orders 1 and 2. Collectors and filter feeders dominate in-stream orders 3 and 4. By examining the LSE elements, it is found that collectors were higher in the streams flowing through areca nut and low in the streams flowing through natural vegetation. The distributions of functional feeding groups within the orders were also analyzed. Mesohabitat results showed scrapers were found to be predominant in riffles whereas collectors, predators, shredders, and filter feeders overwhelm in runs. ANOVA results showed that only mesohabitat was found to be significant. The results of the present study did not broadly concur with the predictions of the River Continuum Concept (RCC) because of the lack of thickly canopied headwater stream sites and the limitation of our study to only EPT taxa.