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Olive-sided Flycatcher - BirdForum Opus

Photo © by Steve Messick
Crow Valley Camp Ground, North-east Colorado, 12 September 2004
Contopus cooperi


18-20 cm (7.1-7.9 in)
The contrasting (off-)white centre line and dark breast sides are diagnostic.

  • Large-billed
  • Heavy-headed
  • Breast and flanks deep olive-brown/dark grey
  • Throat and central breast strongly contrasting (off-)white.
  • Base of tail with white feather tufts
  • Tail broad, notched

Similar Species

Eastern Wood-Pewee and Western Wood-Pewee similar but with longer tails and shorter bills, and they lack blurry breast streaks. Greater Pewee similar but without the vested appearance. Other pewee species such as Dark Pewee and Northern Tropical Pewee are broadly similar, as are empids. All these species lack the strongly contrasting whitish centerline with darker sides ("vest" or "waist coat")


Breeds temperate North America; (Alaska, Canada through to the United States); winters south to Bolivia.


This is a monotypic species[1].

  • Formerly Contopus borealis.
  • Formerly in the genus Nuttallornis.


Boreal forest, and forest edges open wooded areas, riparian sycamore and oak woods, farm fields,

On migration may be seen in rain forest at heights of around 600 m.


They are inclined to perch on the very tops of trees.


The nest is formed from twigs and lined with soft materials, such as lichen, moss and grass. It is placed high up in an evergreen tree, near the end of a branch. The clutch consists of 3 brown-spotted buff eggs.


Diet includes winged insects.


Song is a loud whistled "What PEEVES you?" with the middle note highest and strongly accented. Common call is a "pip-pip-pip" similar to call of Greater Pewee.


Long-distance migrant, wintering in Central and South America; longest migration route of any North American flycatcher.


  1. Clements, J. F., T. S. Schulenberg, M. J. Iliff, S. M. Billerman, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2019. The eBird/Clements Checklist of Birds of the World: v2019. Downloaded from http://www.birds.cornell.edu/clementschecklist/download/
  2. BirdForum Member observations
  3. Farnsworth, A. and D. J. Lebbin (2017). Olive-sided Flycatcher (Contopus cooperi). In Handbook of the Birds of the World Alive (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Lynx Edicions, Barcelona. Retrieved from Handbook of the Birds of the World Alive: https://birdsoftheworld.org/hbw/species/olsfly/1.0
  4. Cornell Lab of Ornithology. 2019. Olive-sided_Flycatcher in: All About Birds. Cornell Lab of Ornithology, Ithaca, New York. https://www.allaboutbirds.org/ Accessed on 27May 2020

Recommended Citation

External Links

GSearch checked for 2020 platform.1