Aquatic plants, as spatial refugia, are used as a tool to enhance wetland biodiversity, because their species richness is positively correlated with aquatic invertebrate species richness. However, little research has investigated how aquatic vegetation cover, i.e. the quantity of prey refugia, affect invertebrate assemblages in predator-prey dynamics. Here we use diving beetles (Dytiscidae) as our study taxon and applied generalised linear mixed models (GLMM) to investigate the effects of emergent plant quantity on invertebrate assemblages in ponds with and without predatory fish. We found that emergent plant cover affected dytiscid assemblages differently at the pond level and the microhabitat level. At the pond level, dytiscid presence was positively correlated with increasing emergent plant cover, both with and without fish, revealing the importance of prey refuge quantity for prey species. At the microhabitat level, dytiscid species richness and abundance responded positively to increasing plant cover in ponds with fish, but there was no such relationship in fishless ponds, indicating that predation pressure affects prey species’ utilisation of microhabitats with and without prey refugia. Our study emphasizes providing variations in emergent plant cover to retain high habitat heterogeneity to support freshwater biodiversity for restoration and conservation purposes.
Keywords: aquatic insect, habitat complexity, macroinvertebrate, predation, urban blue infrastructure
Period1 Feb 20213 Feb 2021
Event titleOIKOS Finland conference 2021: Ecology and Evolutionary Biology in the Changing World – Solutions?
Event typeConference
Degree of RecognitionInternational