These tabular data were compiled to assess full annual cycle breeding of the Empidonax occidentalis (Cordilleran Flycatcher). Objectives of our study was to assess facets of the full annual cycle of the Cordilleran Flycatcher. These data represent over nine field seasons of work on the Dolores River in southwestern Colorado with field work conducted from 2009-2018. These data were collected from 2008-2017 along the Dolores River in southwestern Colorado and were collected by U.S. Geological Survey and University of Arizona employees, many graduate and post-doctoral students. Data were a combination of field observations and video recorded nesting behavior. There was also a permanent weather station at the principal study site (Upper Dolores, UPDO). These data can be used for comparative purposes (e.g., examining global climate change influences on bird breeding) such as changing arrival and departure dates to Mexico form the breeding grounds.