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Theoretical models predict that animals should make foraging decisions after assessing the quality of available habitat, but most models fail to consider the spatio-temporal scales at which animals perceive habitat availability. We tested three foraging strategies that explain how Magellanic woodpeckers (Campephilus magellanicus) assess the relative quality of trees: 1) Woodpeckers with local knowledge select trees based on the available trees in the immediate vicinity. 2) Woodpeckers lacking local knowledge select trees based on their availability at previously visited locations. 3) Woodpeckers using information from long-term memory select trees based on knowledge about trees available within the entire landscape. We observed foraging woodpeckers and used a Brownian Bridge Movement Model to identify trees available to woodpeckers along foraging routes. Woodpeckers selected trees with a later decay stage than available trees. Selection models indicated that preferences of Magellanic woodpeckers were based on clusters of trees near the most recently visited trees, thus suggesting that woodpeckers use visual cues from neighboring trees. In a second analysis, Cox’s proportional hazards models showed that woodpeckers used information consolidated across broader spatial scales to adjust tree residence times. Specifically, woodpeckers spent more time at trees with larger diameters and in a more advanced stage of decay than trees available along their routes. These results suggest that Magellanic woodpeckers make foraging decisions based on the relative quality of trees that they perceive and memorize information at different spatio-temporal scales.

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Artículo de publicación SCOPUSDisentangling the contribution of corridors to landscape connectivity is crucial for adopting efficient measures in conservation, but their actual role in heterogeneous landscapes is not yet fully understood. We assessed the hypothesis that corridors, consisting of hedgerows and riparian vegetation strips, are important landscape elements promoting functional connectivity for the lingue (Persea lingue), a tree endemic to southern Chile and Argentina whose seeds are mainly dispersed by the habitat generalist austral thrush (Turdus falcklandii). For this purpose, we used empirical estimates of seed production, fruit consumption and bird movement patterns, in combination with a seed dispersal model and a graphtheoretical approach for network connectivity analysis. We found that for this plant-animal interaction, the hypothesis mentioned above is not supported. Functional connectivity decreased as the structural connectivity provided by corridors increased, and stepping stones were much more effective connectivity providers than corridors. Our findings are not generalizable to other situations because thrushes contribute to the dispersal of seeds along narrow and sinuous corridors, which provide unsuitable conditions for the establishment of lingues. We conclude that (a) the effectiveness of corridors for promoting connectivity and successful dispersal is landscape- and species-specific; and that (b) effective conservation of Chilean forest biodiversity involves a tradeoff between enhancing the availability of stepping stones and providing corridors of sufficient width and appropriate shape to meet the needs and dispersal modalities of different species.FONDECYT GEFOUR Gran

The abundance of woodland birds in fragmented forest landscapes may depend on the properties of patch networks. Understanding the consequences of deforestation on woodland birds, therefore, necessarily requires determining which changes in landscape structure make a major contribution to the degradation and subdivision of patch networks. In this study, we addressed how accelerated deforestation in central Chile has modified the landscape structure and function for thorn‐tailed rayaditos—a woodland specialist bird. Using a graphical approach based on the habitat use and movement patterns of rayaditos, we quantified the reduction of the internal connectivity of components (i.e., connected patch networks) in the last two decades and determined the main mechanisms responsible for this connectivity loss. Forest cover decreased 61.7 % between 1989 and 2009. The component size, the fraction of components with ≥1 occupied patches and the number of patches per component experienced a large decline during the study period. Over time, most forest cover (ca. 80 %) was contained in only two components. The connectivity of components decreased steeply by 90 %. Only the loss of large patches made a highly significant contribution to explaining changes in connectivity, while the removal of stepping stones was marginally significant. The conversion of forest both to shrubland and to peri‐urban areas were the only land‐use variables explaining connectivity change with effects that changed over time. Conservation measures to ensure persistence of rayaditos populations in central Chile should be focused on the retention of key elements for connectivity.