Scale dependency of joint species distribution models challenges interpretation of biotic interactions

Aim: Separating the biotic and abiotic factors controlling species distributions has been a long-standing challenge in ecology and biogeography. Joint species distribution models (JSDMs) have emerged as a promising statistical framework towards this objective by simultaneously modeling the environmental responses of multiple species and approximating species associations based on patterns in their (co-)occurrences. However, the signature of biotic interactions should be most evident at fine spatial resolutions. Here, we test how the resolution of input data affects the inferences from JSDMs.

Location: Switzerland

Taxon: Birds

Methods: Using standardized survey data of 43 woodland bird species and eight climatic, topographic and vegetation structural predictors, we fit JSDMs at different spatial resolutions (125m to 1000m) and sampling periods (1 and 5years). In addition, we calculate functional similarity among all species as an independent proxy of biotic interactions, specifi...