Short term temporal patterns in a Mediterranean shrubland bird community after wildfire

摘要

The use of a burnt Mediterranean shrubland by birds was investigated during the first three years following a summer fire. Birds were censused by point counts, and vegetation cover was estimated. The results show an early and continuous use of the burnt area by birds. During this period, the variation in avifauna composition relate first to the season, and secondarily to the time elapsed since fire, as shown by Correspondence Analysis of the birds x samples matrix. The main effect of fire is to induce a rapid transition from a shrubland breeding avifauna (dominated by insectivorous species) to a grassland wintering avifauna (dominated by seed-eating species). After fire, the overall abundance of birds at the breeding season is positively correlated with the foliage volume, which seems to be the main limiting factor. Examples of postfire specific responses (colonisation, dispersion, or site tenacity) are shown. Site tenacity of birds, favoured both by the presence of rocky patches and by the persistence of very small unburnt remnants, may explain the relatively moderate effect of fire on this community.