Aves (Birds): Passeriformes, Parulidae
Yellow-breasted Chat (Icteria virens)
Potential Occurrence: Nesting Unlikely to Occur
Status: (Nesting)
Federal: None
State: SSC
Other: G5 S3
Photo: Jim Conrad
Species Description: The largest of the wood
warblers, the Yellow-breasted Chat is 7.5 inches long
and has a 10 inch wingspan (Sibley 2000). Compared to other warblers, this bird has a large bill
and long tail. Olive-brown upper parts and white underparts, with the distinct yellow patch along
the chin, throat, and breast (Eckerle 2001). There are white “spectacles” around the eyes
(Sibley 2000).
Distribution: Breeds in northwestern North America from British Columbia through California,
and has a widespread range in the eastern United States and winters in Mexico from Baja
Calfornia to northern Sinaloa (Hammerson 1996). It is rare or absent in 35% of its historic
breeding range in much of the California’s Central Valley. In northwestern California, Yellowbreasted Chats are widely distributed and are regularly reported on BBS routes in Humboldt,
SIskyou, Shasta, Mendocino, and Lake Counties (Shuford 2008).
Life History & Threats: The Yellow-breasted chat constructs a nest close to the ground (from
ground level to 2 meters) and lays between 3-5 eggs from mid-May to late June (Hammerson
1996). Only the female incubates the eggs and broods the nestlings, but both parents feed the
young (Eckerle 2001). Nestlings fledge in 8-11 days after hatching.
Chats’ dependence on understory and shrubby riparian vegetation for nesting makes them
vulnerable to habitat loss from vegetation removal along river channels during flood-control
maintenance and from urban and agricultural development. (From Shuford 2008)
Brown-headed cowbird is a brood parasite of this species (Eckerle 2001).
Habitat & Habitat Associations:
Nesting Habitat: The Yellow-breasted chat nests in dense shrubs along riparian corridors and in
early-successional open canopy forest (i.e. after a clear cut) (Eckerle 2001; Schuford 2008).
Chats will nest in tamarisk, Himalayan Blackberry (Rubus discolor), Russian Olive (Elaeagnus
angustifolius), and other non-native plants that provide dense shrub layers. (From Schuford
2008)
Conceptual Basis for GIS Model Development: We mapped potential habitat of the Yellowbreasted Chat as riparian vegetation. GIS vegetation layers did not show willow and alder as
occurring along Rancheria Creek, but field reconnaissance indicated that many small patches
and thin corridors of this vegetation type occur on the banks of the Creek. To capture the
occurrence of this habitat types, we mapped riparian vegetation as a 130-m buffer along the
main stem of Rancheria Creek. Riparian woodland, forest and scrub are disjunct within this
area.
Note that small patches of Cottonwood Woodlands do occur immediately north of the Study
Area along Rancheria Creek, but do not occur within the map view.
Potential Occurrence in the Galbreath Wildlands Preserve: Protection status for this species
applies to nesting individuals.
Habitat: Yellow-breasted Chats nest in dense shrubs along riparian corridors. Nesting habitat is
poor to moderate quality in the Preserve (Figure 92). Riparian scrub and woodlands with willows
do occur within the area, but are fragmented and poorly developed due to regular flooding.
Riparian vegetation shown in Figure 92, is an estimate of a zone containing only a patchy
distribution of riparian woodland and scrub. It is uncertain whether any areas of riparian
vegetation are large and dense enough to provide adequate nesting habitat for Yellow-breasted
Chats.
Nearest Occurrence:
Documented Occurrences in the Galbreath Wildlands Preserve: This species has not
been documented on the Preserve. To our knowledge no surveys have been conducted.
Nearest Occurrence to the Galbreath Wildlands Preserve: This species has not been
reported to occur in USGS quads adjacent to the Preserve.
Summary: Nesting Yellow-breasted Chats are “Unlikely to Occur” on the Preserve because
potential nesting habitat is highly fragmented and may not be extensive enough to support
breeding individuals.
References
Eckerle KP, Thompson CF. 2001. Yellow-breasted Chat (Icteria virens), The Birds of North
America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology;
<http://bna.birds.cornell.edu/bna/species/575>. Accessed 2010 Jul 19.
Hammerson G, Dirrigl F, Thompson CF. 1996 Feb 16. Comprehensive Report Species- Icteria
virens. NatureServe Explorer. Version 7.2. <http://www.natureserve.org/explorer/>. Accessed
2010 Jul 18.
Shuford WD, Gardali T, eds. 2008. California Bird Species of Special Concern: A ranked
assessment of species, subspecies, and distinct populations of birds of immediate conservation
concern in California. Studies of Western Birds 1. Western Field Ornithologists, Camarillo,
California, and California Department of Fish and Game, Sacramento.
Sibley DA. 2000. The Sibley Guide to Birds. New York: Alfred A Knopf. p 457.
Species Account Description: Kandis Gilmore & Emily Harvey