Riqueza de aves a lo largo de un gradiente de urbanización en la ciudad de Buenos Aires

Abstract

Bird richness along an urbanization gradient in Buenos Aires city. The bird composition,
richness and foraging guilds along an E-W urbanization gradient in Buenos Aires city is analysed. The gradient
included six green areas where 49 birds have been recorded, 91,8 % of them eco-regional natives. Bird richness
was related to local characteristics of parks, like floristic composition, tree coverage and diversity, roads proximity
and water bodies. Land uses in percentage of coverage for the surroundings of each park were also considered.
The results suggest that green areas located at different levels of urbanization represent important habitats for
native birds. The pattern of bird richness does not conform to the traditional urban- to -rural gradient studies.
Richness shows higher values at both extremes of the urbanization gradient. Especially for bird similarity, the
distance to the «centric» area does not affect much their value. The number of different habitats present in each
park was a suitable indicator for bird richness. Also the quality of the surroundings is an important feature to be
taken into account.