Avian Species Diversity in Desert Scrub

Abstract

Along a gradient of habitat complexity in desert scrub communities of the Sonoran Desert in southern Arizona, nest sites and food niches become more diverse, and breeding bird population density and species diversity increase. Birds are highly specific in their selection of plants for nest placement; densities of nest plants. The MacArthur foliage—height diversity model does not yield consistently accurate predictions of breeding bird species diversities in desert scrub communities. A significant relationship is found between physiognomic coverage diversity and breeding bird species diversity. This index, based on a system of plant life forms, quantifies critical environmental features used by birds in habitat selection. A model that combines aspects of foliage—height diversity and physiognomic coverage diversity may provide greater accuracy and wider applicability for predicting breeding bird species diversity.