Predation risk and habitat complexity modify food web interactions in a tri‐trophic system
Using larvae of several odonate species including both top and intermediate-level predators, we show that the effects of habitat complexity and predation risk on trophic interactions are not additive and in next studies multiple factors should be considered.
Photo description: Habitat complexity provided by submerged aquatic plants and predation risk from large dragonfly larvae (e.g., Aeshna cyanea) can strongly affect aquatic communities. Photo: V. Kolář
Predation risk and habitat complexity (such as the presence of submerged macrophytes) are important biotic drivers of community composition in aquatic ecosystems, but their effects are usually studied in isolation. Using larvae of several odonate species including both a top and intermediate-level predators, we show that the effects of habitat complexity and predation risk on trophic interactions are not additive and depend more on functional traits related to foraging and defence of the intermediate predators and their habitat domains, and that energetic efficiency (ratio between acquired and expedited energy) is mainly determined by predator body mass. We thus suggest that multiple factors should be considered to better understand and predict environmentally driven variations in trophic interactions and functioning of freshwater ecosystems.
Kolář V., Boukal D. S., Sentis A. (2019) Predation risk and habitat complexity modify intermediate predator feeding rates and energetic efficiencies in a tri‐trophic system. Freshwater Biology. DOI: 10.1111/fwb.13320