Efforts to disentangle the mechanisms underlying large‐scale spatial patterns need to rely on multi‐scale approaches. We illustrate this key issue by analyzing the spatial consistency across scales of the effects of abiotic constraints on the regeneration of English yew Taxus baccata in Europe. We hypothesized that the recruitment rates in a given population would be strongly affected by water availability, which should result in a predictable pattern of regeneration success at regional and continental scales. Accordingly, we predicted: 1) at the regional scale water availability should be higher in sites occupied by yew populations than in random locations; 2) at the regional scale regeneration success should decrease when water availability is lower; and 3) at the continental scale, regeneration success should also decrease where water availability is lower, resulting in decreasing regeneration southwards. To test these predictions we first monitored seedling emergence and survival in two central Spanish populations over two years, and confirmed that yew recruitment is limited by water availability. Additionally, our analysis supported predictions 1 and 2: water availability strongly affected yew presence and regeneration success. At the continental scale (prediction 3), our results confirmed lower regeneration in southern European populations. Assessing the effect of climatic constraints across scales in key population parameters can help to improve large‐scale assessments of impacts of climate change on biodiversity.

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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.

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