Aves (Birds): Passeriformes, Tyrannidae
Olive-sided Flycatcher (Contopus cooperi)
Potential Occurrence: Nesting Likely to Occur
Status: (Nesting)
Federal: none
State: SSC
Other: USFWS BBC
Synonym: Prior to 1997, this species was called Contopus
borealis (Wikipedia 2010)
Species Description: The Olive-sided Flycatcher is 6.25
inches long, with a triangular head, relatively short tail, and
stout bill (Gough 1998).
Photo: © Marshall Faintich
Plumage deep brownish olive-gray above (darkest on crown), and white on throat and center of
breast and belly, with strongly contrasting olive-gray sides and flanks (often streaked). Dark
patches on either side of white breast and belly are distinctive and often likened to appearance of
an unbuttoned vest.” (From Altman 2000)
Distribution: This bird’s breeding range extends from Alaska and the Yukon south to Baja
California. It breeds throughout northern California except for the central valley and eastern
deserts (Altman 2000).
Life History & Threats: The Olive-sided Flycatcher breeds in North America and Canada and
winters primarily in Panama and the Andes mountains in South America (Altman 2000). In
California, a clutch of 3-4 eggs is laid in late May to early July, incubation lasts 14-19 days, and
young leave the nest between 15 and 23 days after hatching (Gotthardt 2008). The Olive-sided
Flycatcher’s diet consists of insects, which it hunts by flying in a “yo-yo pattern” perching at the
tallest point of a snag, swooping down to attack, and then returning to its perch (Altman 2000).
In the past 30 years this species has experienced significant declines in populations throughout
its range, causing it to be listed as a Sensitive Species or Species of Concern by several federal
and state agencies and conservation groups. Until recently, most life-history information on Olivesided Flycatchers was anecdotal. Recent species-specific research on habitat relationships and
nesting ecology in Alaska (Wright 1997), Colorado (Kotliar and Melcher 1997, 1998), and Oregon
(Altman 1998, 1999) has advanced our knowledge about the species substantially. (From
Altman and Salabanks 2000)
Habitat & Habitat Associations:
Foraging Habitat:
Primarily montane and northern coniferous forests, usually at mid- to high-elevations. Within
coniferous forest biome, most often associated with forest openings, forest edges near natural
openings (e.g., meadows, bogs, canyons, rivers) or human-made openings (e.g., harvest units),
or open to semi-open forest stands. Presence in early successional forest appears dependent on
availability of snags or residual live trees for foraging and singing perches. Frequently occurs
along wooded shores of streams, lakes, rivers, beaver ponds, bogs and muskegs, where natural
edge habitat occurs and standing dead trees often are present. (From Cornell Ornithology Lab
2010)
Nesting Habitat: Red spruce (Picea rubens) balsam fir, tamarack and eastern hemlock (Tsuga
canadensis) are commonly found near nesting sites (Gotthardt 2008). Douglas fir forests
(Pseudotsuga menziesii) in northern California. Uses lichens from the genus Usnea in nest
building (Altman 2000).
Female appears to choose nest site, although some males suggest locations by repeatedly flying
to certain branches while female is nearby and bellying down into foliage as if molding lining of a
nest. Generally saddled on top of a horizontal branch, well out toward the tip, often where
overhanging branch provides some security and protection from weather. Most nests in
coniferous trees, although observed in trembling aspen and willow. (From Cornell Ornithology
Lab 2010)
Special Habitat Features: Extensive use of snags for aerial attack of prey and territorial singing
(Gotthardt 2008).
Conceptual Basis for GIS Model Development: To identify potential habitat for the Olivesided Flycatcher in the Study Area, we mapped:
General Habitat: as all types of cismontane, broadleaf upland, and coniferous forest vegetation.
Best habitat was mapped as areas in the above vegetation types with:

open to moderately closed canopy (< 70% canopy cover)

streams and ponds (seasonal and perennial)
Nesting Habitat: Douglas Fir
Foraging Habitat: Snag locations are not mapped in a GIS data layer.
Potential Occurrence in the Galbreath Wildlands Preserve:
species applies to nesting individuals.
Protection status for this
Habitat: In northern California, Olive-sided Flycatchers nest in Douglas Fir forests and prefer to
forage in areas with open or moderately open canopies near streams and ponds. Nesting
habitat is abundant in the Preserve and good quality (Figure 94).
Nearest Occurrence:
Documented Occurrences in Preserve: This species has not been documented in the
Preserve. To our knowledge, no surveys have been conducted.
Nearest Occurrence to Preserve: This species has not been reported to occur in USGS
quads adjacent to the Preserve, but is known to occur throughout California.
Summary: We anticipate that nesting Olive-sided Flycatchers are “Likely to Occur” in the
Galbreath Wildlands Preserve due to abundant high-quality nesting habitat.
References
Altman B, Sallabanks R. 2000. Olive-sided Flycatcher (Contopus cooperi), The Birds of North
America Online. Ithaca: Cornell Lab of Ornithology. <http://bna.birds.cornell.edu/bna/species/
502> 2010 July 9.
Author unknown. 2010 Feb 11. Olive-sided Flycatcher. Wikipedia. <http://en.wikipedia.org/wiki/
Olive-sided_Flycatcher> 2010 July 8.
Cornell Ornithology Laboratory 2010. Olive-sided flycatcher (Contopus cooperi). Birds in
Forested Landscapes. The Cornell Lab of Ornithology. Ithica, New York.
<http://www.birds.cornell.edu/bfl/speciesaccts/olsfly.html> 2010 July 10.
Gotthardt TA, McClory JG, Hammerson G, Cannings S. 2008 Jan 03. Comprehensive Report
Species- Contopus cooperi. NatureServe Explorer. Version 7.1. <http://www.natureserve.org/
explorer> 2010 July 8.
Gough G, Sauer JR, Iliff M. 1998. Olive-sided Flycatcher. Patuxent Bird Identification Center.
<http://www.mbr-pwrc.usgs.gov/id/framlst/i4590id.html> 2010 July 8.
Photo info: Published by the US Forest Service, this photo is in the public domain.
<http://commons.wikimedia.org/wiki/File:OlivesidedFlycatcher23.jpg> 2010 July 8.
Species Account Description: Kandis Gilmore and Emily Harvey