EXCAVATED CAVITIES AS FOREST LEGACIES THAT AFFECT SPACE USE BY A LARGE-SIZED WOODPECKER

SOTO, G.E., RODEWALD, A. D., VERGARA, P.M., OJEDA, V. AND CHAZARRETA, L; +3 AUTORES; OJEDA, V

Congreso; XIII Congreso Chileno de Ornitología; 2022

Spatial configuration of resources directly affects the occurrence and abundance of organisms in ways that can influence long-term population dynamics, especially when space and/or resources are limited. In this study we explored how the spatial distribution of excavated cavities affect habitat use within territories of magellanic woodpeckers (Campephilus magellanicus). This territorial, decayed wood specialist inhabits South American temperate forests. Magellanic woodpeckers roost, though rarely nest, in preexisting cavities. We hypothesized that the availability of previously excavated cavities, along with quality of foraging habitat and the configuration of neighboring territories, would determine how particular pairs/families use their territories. We assessed the spatial configuration of trees with cavities inventoried from two monitored woodpecker populations of ca. 8 woodpecker families each, one from northern Argentine Patagonia, and the other from southernmost Chile, and found high levels of spatial clustering. We used weighted distribution models to measure the individual and combined effects of stand/patch decay (based on satellite imagery) and cavity availability on space use within individual woodpecker home ranges. In both study areas, the Utilization Probability Distributions (UD; intensity of use of specific areas within territories), increased with cavity availability. Marginal effects were also found for neighboring woodpeckers and for decay within home ranges.cavity nesting, territoriality, woodpeckers