Breeding bird communities were studied by line-transect in burnt pinewood and unburnt pinewoods, during three\ud years subsequently to a fire event, in a coastal woodland of Mediterranean central Italy. We analyzed data following a diversity/\ud dominance approach that ranks the species in order of their abundance, to obtain rank/abundance diagrams (‘Whittaker\ud plots’). Although it is generally accepted that fire may induce structural changes in forest communities of breeding birds, we\ud observed more evident effects when considering the assemblage of forest-specialist species. When considering the whole\ud community of birds, ordinate intercepts of the regression between rank and relative abundance of species were not significantly\ud different between unburnt and burnt plots in any of the three years of study. However, when considering only the forest-related\ud species, there was a significant difference between unburnt and burnt plots in all the years of study. Evenness showed lower\ud values that were explicited by the diversity/dominance diagrams (lower collocation of the curves of burnt pinewoods if compared\ud to unburnt ones). Overall, the patterns observed in this study suggest that the effects of fire disturbance were more evident\ud at the ecological level than at the taxonomic-level assemblages. The gradual decline of the more sensitive species due to fires\ud and the proportional increase of edge/generalist species may induce a species turnover in burnt woods with cascade and relaxation\ud effects which could be evidenced by diversity/dominance diagrams. Consequently, it is useful to separate the effects of\ud fires at community-level and at assemblage-level when studying bird communities in areas subjected to fire

Breeding bird communities in burnt and unburnt residual pinewoods were studied over 3 years by line-transect method, following a catastrophic fire event in Castelfusano (Rome, Central Italy; July 2000). We applied bootstrap procedures to evaluate whether the observed data were true or just produced by chance, and then examined the emerging patterns at three levels: community, guild and species levels. At the community level, fire acted on breeding bird communities by altering especially the total abundance patterns: the species abundance decreased in the burnt pinewood compared to the residual one, but other parameters were not significantly affected by fire. As a consequence of fire, the destruction and structural simplification of the canopy and shrubby component, as well as the increase of edge habitat and patchiness at landscape scale, induced a turnover in species between pinewoods. Species turnover was higher at the burnt than at the residual pinewoods, during all the 3 years of study. At the guild level, the forest species decreased strongly in terms of richness and abundance in the burnt pinewoods, contrary to the edge and open habitat species which increased in terms of richness, abundance and evenness. Edge species showed the highest turnover in burnt pinewood during the whole period of study. At species level, after an a priori subdivision (based on bibliographic search) of the various species in two ecological guilds (forest versus edge species), it was found that an a posteriori statistical analysis confirmed the expected trend, i.e. that the species which decreased significantly in burnt pinewood were essentially the forest species, whereas the species which increased were essentially the edge/open habitat ones. Overall, in order to investigate the effects of fire catastrophes on birds, the guild approach seems more exhaustive than the taxonomic community approach, where intrinsic confounding trends are presen

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