Ecological interactions between plants and animals have been studied for some time. Mutualistic interactions, such as pollination or seed dispersal, have received particular attention. Recently, network theory has provided a framework to study the organization of interactions within entire communities. Consequently, the static structural picture of mutualistic networks is presently well understood. The next step is to understand how they vary in space and time. Our central question is whether variation in the disperser community creates variation in the ecological functionality of mutualistic networks. In this study, we focus on an endangered conifer, Taxus baccata L., and its associated frugivorous community in three populations over two consecutive years.

Results/Conclusions

We find a highly-variable frugivorous community in both in the number and identity of species. On the other hand, we find consistent patterns of seed deposition between populations and across years. We argue that the identity of the species that disperse the seeds is not as relevant as the ecological role they play. In our study sites, some frugivorous species display similar foraging behaviors, such as microhabitat selection. Therefore, the absence of particular frugivore species may not have strong implications on seed dispersal so long as ecologically similar species continue to disperse the seeds. Disentangling the importance of species identity and ecological roles is a fundamental issue in conservation efforts.