Technical Report
Southwestern Willow Flycatcher Breeding Site and Territory Summary - 2012
Date: 2017/08/01
Author(s): Durst S.L.
Publication: Prepared by U.S. Fish and Wildlife Service, 40 p.
Abstract:
The Southwestern Willow Flycatcher (Empidonax traillii extimus; hereafter references to Willow Flycatcher and flycatcher refer to E. t. extimus except where specifically noted) is an endangered bird that breeds only in dense riparian habitats in six southwestern states (Arizona, New Mexico and southern portions of California, Colorado, Nevada, and Utah,). Since 1993, thousands of flycatcher surveys have been conducted, and many new flycatcher breeding sites located. This document synthesizes information available through 2012 on all known Southwestern Willow Flycatcher breeding sites. The range-wide database that is the basis for this summary report had not been updated since 2007 (Durst et al. 2008) and information presented herein includes data from surveys conducted at many sites since the 2007 update.
This rangewide data synthesis was designed to meet these objectives: 1 – identify all known Southwestern Willow Flycatcher breeding sites, and 2 – assemble data to estimate population size, location, habitat, and other information for all breeding sites, for as many years as possible, from 1993 through 2012.