The effects of vegetation cover on the structure of bird communities in a hyperarid desert

Abstract

The hyperarid deserts of Wadi Araba, SW Jordan, include a variety of habitats ranging from barren alluvial fans and sand dunes to arid acacia savannahs and salt marshes. The diversity of resident birds was highest in acacia stands growing on alluvial fans and stone plains. Although open sand dune habitats have a distinct bird community contributing to the overall diversity, the local diversity within these habitats is relatively small. In habitats with both rocky and sandy substrates, species richness, avian abundance and the diversity of feeding guilds increased locally with the density of shrubs and/or trees. Additionally, avian diversity was related to vertical structure and linked to the mean height of shrubs and trees. Ephemeral annual cover had no general effect on the diversity of the native bird community. Shrub and tree cover appear to be reliable habitat cues used by many bird species when choosing their breeding habitats, as the presence of shrubs and trees increases the diversity of food resources and of secure nesting sites.