Seed dispersal in heterogeneous landscapes: Linking field observations with spatially explicit models

Abstract

Seed dispersal by animals drives persistence and colonization of the majority of fleshy-fruited plants. Different factors have been identified as important in shaping patterns of seed deposition. These factors include habitat heterogeneity, movement patterns of frugivore species, and their feeding behavior. Most studies, however, have analysed the effect of one factor at the time, either with a modelling approach or from field observations. Here, we combine empirical data with spatially-explicit models to explore the contribution of habitat availability and patterns of frugivore post-feeding flight distances to the spatial patterns of seed dispersal. We found that both factors, distance from the mother tree and microhabitat identity, were shaping those patterns. Our results show that seed dispersal is tremendously heterogeneous and complex in space. The observed seed shadow is not the result of a single process but instead an intricate combination of distance and habitat selection. We suggest that the apparent combination of processes results from the simultaneous effects of distinct functional groups of frugivores.