Technical Report

Vegetation Quantification of Southwestern Willow Flycatcher Next Sites: Rio Grande From La Joya to Elephant Butte Reservoir Delta, New Mexico - 2004-2006

URL: https://webapps.usgs.gov/mrgescp/documents/Technical%20Service%20Center_2007_Vegetation%20Quantification%20of%20SWFL%20Nest%20Sites%20Rio%20Grande%20from%20La%20Joya%20to%20Elephant%20Butte%20Reservoir%20Delta%2C%20NM-2004-2006.pdf

Date: 2007/03/01

Author(s): Reclamation

Publication: U.S. Bureau of Reclamation Report, 11 p.

Abstract:

The Bureau of Reclamation (Reclamation) has been conducting studies of the endangered Southwestern Willow Flycatcher (Empidonax traillii extimus - SWFL) along several reaches of the Middle Rio Grande since 1995. Currently, breeding SWFLs are concentrated in suitable habitat within the conservation pool of Elephant Butte Reservoir and in a few isolated areas upstream including the Pueblo of Isleta, La Joya State Wildlife Area (SWA), Sevilleta National Wildlife Refuge (NWR), and the reach between Bosque del Apache NWR and San Marcial. During the past eight years, the SWFL population in the pool of Elephant Butte Reservoir has increased dramatically by dispersing into new, primarily native riparian habitat.

To facilitate recovery of this endangered subspecies in the Middle Rio Grande, it is necessary to understand habitat relationships and features selected by breeding SWFLs. This will assist us to effectively protect, maintain, create, restore, and/or enhance riparian habitats in this area. This report summarizes our efforts to characterize vegetation features of selected SWFL nest sites documented during presence/absence surveys and nest monitoring between 2004 and 2006.