From 1996 to 2005, the U.S. Geological Survey (USGS) conducted a demographic study of the Southwestern Willow Flycatcher (Empidonax traillii extimus) in Arizona in collaboration with the Arizona Game and Fish Department (AGFD). The study was begun the year following the listing of the Southwestern Willow Flycatcher as an endangered species. At the time of the listing, very little was known about the biology and threats to the flycatcher, and one of the main objectives of the study was to gather detailed long-term information on the biology of the flycatcher.
This report is organized into eight chapters. Following the introductory chapter, we deal with specific aspects of flycatcher ecology and habitat use in each of six separate chapters. We end with a concluding chapter that synthesizes information into broad topical themes that address key management issues. Each of the core chapters (chapters 2 through 7) conclude with a list of management considerations derived from the findings of the respective chapter.