Identifying key species in meta-communities

With the ongoing biodiversity crisis, identifying which species are of particular importance to prevent the extinction of other species has become a pressing issue. However, most approaches to detect these important species are made at a local (i.e, community) level, without considering the potential effect of species dispersion in a landscape. We present a modified PageRank algorithm to determine the importance of species in meta-communities based on two sets of networks: food webs that depict local trophic interactions and landscape networks representing the movement of species across different habitat patches. We show that (i) what is considered an important species changes between isolated communities and meta-communities and (ii) the importance of a species in a meta-community depends on the position of its habitat patch in the landscape network. Our results stress the need for a global consideration of space in the identification of important species.