Abstract
While species interactions are fundamental for linking biodiversity to
ecosystem functioning and for conservation, large-scale empirical data
are lacking for most species and ecosystems. Accumulating evidence
suggests that trophic interactions are predictable from available
functional trait information, but we have yet to understand how well we
can predict interactions across large spatial scales and food webs.
Here, we built a model predicting predator-prey interactions based on
functional traits for European vertebrates. We found that even models
calibrated with very few known interactions (100 out of 71k) estimated
the entire food web reasonably well. However, predators were easier to
predict than prey, with prey in some clades being particularly difficult
to predict (e.g., fowls and storks). Local food web connectance was also
consistently over-estimated. Our results demonstrate the potential for
filling gaps in sparse food webs, an important step towards a better
description of biodiversity with strong implications for conservation
planning.