Effects of prey abundance and foliage structure in plant selection by insectivorous birds in the central Monte desert

Foraging behavior allows a direct examination of how birds use their habitats and provides the possibility to understand what environment factors can determine those patterns. We analyzed the woody plant selection, height and substrate use, and attack maneuver by Greater Wagtail-tyrant ( Stigmatura budytoides ), Grey-crowned Tyrannulet ( Serpophaga griseicapilla ) and Ringed Warbling-Finch ( Microspingus torquata ) in the main habitats of central Monte desert. The three bird species selected Prosopis flexuosa trees and avoided the most abundant shrub species: Larrea divaricata and Larrea cuneifolia in mesquite woodland and creosotebush habitats. The importance of P. flexuosa was due because this plant constitute an abundant food patch of great diversity of arthropods. Our results about how bird species use their habitat and which factors were influencing these selection pattern are important to management and conservation of insectivorous birds in the central Monte desert.