Willow Flycatcher – State Wildlife Action Plan

Willow Flycatchers are a small, slender flycatcher and are one of the larger members of the genus Empidonax. Due to strong similarities in appearance to other Empidonax flycatchers, they can be difficult to identify in the field without vocal cues. They are brownish olive overall with a slight yellow tint to the belly. Willow Flycatchers have two whitish wing bars and a white throat; their white eye ring is very narrow to nonexistent. They have a large, broad bill and dark feet. Males are not distinguished from females in appearance. Often perches on high or the tops of bushes to sing ‘fitz-bew’ song or call with a soft ‘whit’. Oregon is home to two recognized subspecies of Willow Flycatcher. E. t. adastus on the east side of the Cascade Range is paler and greener above, more greyish in the upper breast, and has paler tertial and secondary feather edges than E. t. brewsteri which inhabits lands west of the Cascades.

Overview

Species Common Name Willow Flycatcher
Species Scientific Name Empidonax traillii
Federal Listing Status Species of Concern
State Listing Status Sensitive

Ecoregions

Northern Basin and Range

The Northern Basin and Range ecoregion covers the very large southeastern portion of the state, from Burns south to the Nevada border and from the Christmas Valley east to Idaho. It is largely a high elevation desert-like area dominated by sagebrush communities and habitats.

Willamette Valley

The Willamette Valley ecoregion is bounded on the west by the Coast Range and on the east by the Cascade Range. This long mostly level alluvial plain has some scattered areas of low basalt, and contrasts with productive farmland and large urban areas. It has the fastest-growing human population in the state resulting in challenges due to land-use changes.

Special needs

Willow Flycatchers are dependent upon riparian shrub habitat. They require a dense, continuous or near-continuous shrub layer, especially of willows. They may also occur in forest openings.

Limiting factors

Willow Flycatchers have experienced steep population declines in Oregon in recent decades. Loss and degradation of riparian shrub habitat, in part due to altered hydrological regimes and invasive species, have contributed to these declines. Breeding habitat of Willow Flycatchers in Oregon is threatened by cattle grazing, habitat conversion, and alteration of hydrology. Destruction and degradation of habitat by livestock grazing has also been noted as a source of significant decline across the species’ range. Overgrazing of riparian areas and wet meadows may cause soil compaction, gullying, streambank trampling, loss of woody vegetation, or invasion of non-native species. Throughout the Pacific Northwest, wetland complexes, floodplains, and riparian zones have been substantially altered and converted to agricultural land uses. Habitat isolation is a concern for Willow Flycatchers because of the patchy nature of their breeding habitat. Brown-headed Cowbird (Molothrus ater) parasitism may also adversely affect breeding success.

Data gaps

• Continue to assess abundance and trends.
• Identify site and landscape factors that contribute to Brown-headed Cowbird parasitism.
• Assess impacts to insect prey base.
• Assess habitat use.

Conservation actions

• Restore brushy patches of willow and other native shrubby habitats near water.
• Control non-native plants to improve native shrub plant communities.
• Discourage Brown-headed Cowbird use of riparian areas through seasonal timing of grazing and/or maintaining high grass heights in priority areas.
• Restore riparian and early seral/montane meadow habitat in the West Cascades.

Key reference or plan

PIF Focal Species. Rockwell et al. 2021. Read here

Conservation Assessment of the Willow Flycatcher in the Sierra Nevada. 2003. Read here