BIRD HABITAT RELATIONSHIPS IN AN URBAN PARK DURING WINTER

Relationships between habitat characteristics and bird distribution we re investigated during winter in El Retiro Park, Madrid (Spain). Princ ipal Component Analysis of habitat variables gave three significant fa ctors: structural complexity gradient (PC1), habitat availability for people transit in relation to vegetation management (PC2) and tree hei ght (PC3). Analysis of the relationships between main community parame ters (density, species richness and diversity) showed that bird densit y was closely associated with human influences on habitat as well as h uman presence (PC2), especially with respect to Passer domesticus and Columba livia. The vertical structure of vegetation in association wit h the cover of conifers (PC3) is the factor that better predicts diver sity. Species richness was not related with any habitat component nor by individual habitat variables. Thus, our results suggest that althou gh the physiognomical and floral structure of the park has an effect o n the avian community structure, its influence is dependent of vegetat ion management and human presence.