Constructing a food web from inventory data in a boreal forest-dominated national park in south-eastern Sweden

Abstract: A food web was constructed for a boreal-forest dominated national park in south-eastern Sweden, called Tyresta national park and its surrounding nature reserve. Due to increasing threats to mammalian species and their critical role in the food web mammals were used as the outset of the food web, and from there branching out to taxa trophically interacting with mammals directly and indirectly. The outset of the food web was constructed using available inventory data, focusing on mammals. From inventory data and 53 interaction sources, consisting of mostly primary literature a food web was created that includes 32 mammalian taxa, six bird families, five invertebrate taxa, fish, amphibians, fungi, reptiles, detritus and 9 different basal plant taxa. The results of the literature review was that the most consumed staple taxon of all were hexapods, with it being a staple food for 15 taxa, six of them being bats preying mainly on dipterans. There are a wide variety of ways that interspecific competition could come to affect taxa in the study area, for example through intraguild predation, increased dietary breadth or avoidance, or a combination of these. This method could serve as a complement to existing food webs or the construction of new ones in a cheaper, less intrusive and less time-consuming way, albeit missing local adaptations. The constructed food web structure and findings of interspecific competition in Tyresta can be used for further analyzing certain links or branching the web out even further, with increased depth or quantification of certain taxon.