olive-sided flycatcher

The olive-sided flycatcher is a small to medium-sized passerine, smaller than an American robin, but bigger than sparrows. It can be identified by its olive-grey or grey-brownish plumage above with a white mid-breast section and throat. The olive tones on its back and wings are seen mainly in optimal light and when the feathers are freshly moulted. The sides of the breast area are grey and make the bird look like it is wearing a vest. It has a relatively long bill and long wings for its size. Sometimes, some of its head feathers can be raised, which make it look like it has a small crest. Male and female look similar. Olive-sided flycatchers perch in upright positions on top of dead branches or trees.{{Cite web|title=Olive-sided Flycatcher Identification, All About Birds, Cornell Lab of Ornithology|url=https://www.allaboutbirds.org/guide/Olive-sided_Flycatcher/id|access-date=2021-11-10|website=www.allaboutbirds.org|language=en}}

Olive-sided flycatchers can be confused with other birds in the genus Contopus like the greater pewee, western wood-pewee, eastern wood-pewee, and with the eastern phoebe. They can be distinguished these species by observing the following differences: the plain grey breast of the greater pewee (as opposed to the vest-like chest of the olive-sided flycatcher); size, the olive-sided flycatcher being twice the weight of the western and eastern wood pewees; and the whiter underparts of the eastern phoebe.

Olive-sided flycatchers (Contopus cooperi) are in the order Passeriformes (perching birds). They are part of the family Tyrannidae, the New World or tyrant flycatchers, and the genus Contopus, the pewees. Pewees are insect eaters that generally catch their prey in flight.{{Cite journal|last=International)|first=BirdLife International |date=2016-10-01|title=IUCN Red List of Threatened Species: Contopus cooperi|url=https://www.iucnredlist.org/en|journal=IUCN Red List of Threatened Species}}

The species has often been considered to be monotypic; the Clements Checklist and AOS Checklist of North American Birds currently do not recognize any subspecies. However, the disjunct populations that breeds in southern California and Baja California is sometimes recognized as a distinct subspecies, C. cooperi majorinus.{{Cite book |last=Pyle |first=Peter |url=https://www.worldcat.org/oclc/38593534 |title=Identification guide to North American birds : a compendium of information on identifying, ageing, and sexing "near-passerines" and passerines in the hand |date=1997 |publisher=Slate Creek Press |others=Steve N. G. Howell, Siobhan Ruck, Institute for Bird Populations, Point Reyes Bird Observatory |isbn=0-9618940-2-4 |location=Bolinas, Calif. |oclc=38593534}}{{Cite journal |last1=Altman |first1=Bob |last2=Sallabanks |first2=Rex |date=2020 |title=Olive-sided Flycatcher (Contopus cooperi), version 1.0 |url=https://birdsoftheworld.org/bow/species/olsfly/cur/introduction |journal=Birds of the World |language=en |doi=10.2173/bow.olsfly.01|url-access=subscription }} This subspecies is a short-distance migrant and has longer wings and tail feathers than birds from elsewhere.{{Cite web |title=Olive-sided Flycatcher Identification, All About Birds, Cornell Lab of Ornithology |url=https://www.allaboutbirds.org/guide/Olive-sided_Flycatcher/id |access-date=2023-02-24 |website=www.allaboutbirds.org |language=en}}

The olive-sided flycatcher is distributed throughout North and South America. Its breeding habitat ranges from California and New Mexico all the way up to central Alaska, then across Canada (except for most of the Northwest Territories and Nunavut) and through a portion of northeastern US. Its non-breeding habitat is mainly in the northern part of South America and a small area in Central America.{{Cite web|title=Olive-sided Flycatcher Range Map, All About Birds, Cornell Lab of Ornithology|url=https://www.allaboutbirds.org/guide/Olive-sided_Flycatcher/maps-range|access-date=2021-11-11|website=www.allaboutbirds.org|language=en}}

Their breeding habitat is mainly in open areas or edges of boreal, coniferous forests or temperate western forests, in areas up to 10,000 feet in elevation (e.g., in the Rockies), and always near water. They can also nest in cities or on farms. In their non-breeding habitat, olive-sided flycatchers use similar habitats as their breeding habitats, such as open areas and forest edges, but do not need water proximity as much as in their breeding habitat. They are also associated with habitats with very tall trees.{{Cite web|title=Olive-sided Flycatcher Life History, All About Birds, Cornell Lab of Ornithology|url=https://www.allaboutbirds.org/guide/Olive-sided_Flycatcher/lifehistory|access-date=2021-11-11|website=www.allaboutbirds.org|language=en}} Two forest habitats used by olive-sided flycatchers in the winter are tropical montane and tropical lowland evergreen forests.{{Cite web|title=Avian Conservation Assessment Database Scores – Partners in Flight Databases|url=https://pif.birdconservancy.org/avian-conservation-assessment-database-scores/|access-date=2021-11-12|language=en-US}}

During the breeding, olive-sided flycatcher males sing a song to attract a mate. The mnemonic for its song is "Quick, three beers!" with three successive higher-pitched sounds. The first sound is shorter and not as high-pitched and loud as the two others. Sometimes, during mating season, males can produce growling sounds or squeaks when in conflict with other males. This species' most frequent call is three quick successive pip sounds.{{Cite web|title=Olive-sided Flycatcher Sounds, All About Birds, Cornell Lab of Ornithology|url=https://www.allaboutbirds.org/guide/Olive-sided_Flycatcher/sounds|access-date=2021-11-11|website=www.allaboutbirds.org|language=en}}

The rate at which males sing varies throughout the breeding season. This variation appears to be correlated indirectly with the breeding status (single, paired, or feeding young) of the individuals.{{Cite journal|last1=Upham-Mills|first1=Emily J.|last2=Reimer|first2=Jody R.|last3=Haché|first3=Samuel|last4=Lele|first4=Subhash R.|last5=Bayne|first5=Erin M.|date=2020|title=Can singing rate be used to predict male breeding status of forest songbirds? A comparison of three calibration models|journal=Ecosphere|language=en|volume=11|issue=1|pages=e03005|doi=10.1002/ecs2.3005|issn=2150-8925|doi-access=free|bibcode=2020Ecosp..11E3005U }}

Olive-sided flycatchers breed once per year and usually lay clutches of 3 to 4 eggs. The incubation period lasts for 15 to 19 days and so does the nestling stage. The egg is approximately 0.8–0.9 inches long by 0.6–0.7 inches wide and is a creamy white colour with brownish spots that form a ring on the larger end of the egg. The nest location is chosen by the female and is usually on a horizontal branch of coniferous trees, but they have also been seen on other types of trees. The lowest nest was 5 feet high and the highest was 197 feet. In Western regions, olive-sided flycatchers tend to have higher nests than in their Eastern distributions. The nest is about 4.6 inches wide on the outside and 2.8 inches wide on the inside and is cup-shaped. The outer part is made with twigs and small branches, while the inside is usually lined with finer material such as grass, lichen, and needles. The hatching are born naked and helpless. The male defends a large area around the nesting territory. Both parents feed the young birds.

File:Olive-sided Flycatcher Sabine Woods High Island TX 2018-04-26 09-20-44 (41190510985).jpg

Hawking is the main feeding method used by olive-sided flycatchers. They feed on flying insects (e.g., bees, wasps, moths, beetles, grasshoppers, etc.) and capture them in the air. They will sometimes feed on fruit during migration and non-breeding season.

During parental care, olive-sided flycatchers consume its chicks' fecal sacs. Both sexes do so within the first week of hatchings' lives, then start to remove them from the nest. This behaviour is thought to supplement the parental nutrition.{{Cite journal|last1=Hagelin|first1=Julie C.|last2=Busby|first2=Shannon|last3=Harding-Scurr|first3=April|last4=Brinkman|first4=Aleya R.|date=2015-06-01|title=Observations on Fecal Sac Consumption and Near-ground Foraging Behavior in the Olive-sided Flycatcher (Contopus cooperi)|url=https://doi.org/10.1676/wils-127-02-332-336.1|journal=The Wilson Journal of Ornithology|volume=127|issue=2|pages=332–336|doi=10.1676/wils-127-02-332-336.1|s2cid=83775008 |issn=1559-4491|url-access=subscription}}

Of all the flycatcher species that breed in the United States, the olive-sided flycatcher has the longest migration. Some olive-sided flycatchers migrate up to 7,000 miles traveling between central Alaska and Bolivia.{{Cite web|title=Olive-sided Flycatcher Overview, All About Birds, Cornell Lab of Ornithology|url=https://www.allaboutbirds.org/guide/Olive-sided_Flycatcher/overview|access-date=2020-09-27|website=www.allaboutbirds.org|language=en}}

According to the IUCN Red List in 2016, the olive-sided flycatcher is classified as a Near Threatened species. This conservation status is assigned when the taxon does not fit within the Critically Endangered, Endangered or Vulnerable categories, but is likely to fit within one of them in the near future.{{Cite book|url=https://portals.iucn.org/library/node/10315|title=IUCN Red List categories and criteria, version 3.1, second edition|date=2012|publisher=IUCN|isbn=978-2-8317-1435-6|language=en}} The Canadian Species at Risk Act lists the olive-sided flycatcher as threatened due to its declining population.{{Cite web|last=Branch|first=Legislative Services|date=2021-08-12|title=Consolidated federal laws of canada, Species at Risk Act|url=https://laws-lois.justice.gc.ca/eng/acts/S-15.3/section-sched435646.html?txthl=olive-sided+flycatcher+olive|access-date=2021-11-12|website=laws-lois.justice.gc.ca}}

The olive-sided flycatcher's global population is estimated at 1.9 million individuals but appears to be declining at a rate of 3% of the population per year and has declined by 79% in the past 50 years.

With climate change becoming increasingly important and causing important changes in the ecosystems, a study in Nova Scotia predicted climate-resilient habitats that would be suitable for olive-sided flycatchers. The authors built a model that considered mean canopy height as the most important factor for this species because it needs a habitat with tall trees. The results suggest that the relative habitat suitability for olive-sided flycatchers in the area of the study will increase with canopy height and decrease as the habitat moves further away from conifer-dominated forests and areas with dead material, which is known to be crucial for their feeding habits. This species is also expected to prefer valleys, lowlands and flatter areas, which have the potential to form wetlands or streams. The results from this study determined that the forests used in Nova Scotia have a high potential for olive-sided flycatcher populations to be resilient to climate change.{{Cite journal|last1=Bale|first1=Shannon|last2=Beazley|first2=Karen F|last3=Westwood|first3=Alana|last4=Bush|first4=Peter|date=2020-03-10|title=The benefits of using topographic features to predict climate-resilient habitat for migratory forest landbirds: An example for the rusty blackbird, olive-sided flycatcher, and Canada warbler|journal=The Condor|language=en|volume=122|issue=1|pages=duz057|doi=10.1093/condor/duz057|issn=0010-5422|doi-access=free}}

Research in Eastern Canada showed that disturbances caused by human activities and road proximity have a negative impact on olive-sided flycatcher populations in Canadian national parks.{{Cite journal|last1=Westwood|first1=Alana R.|last2=Staicer|first2=Cindy|last3=Sólymos|first3=Péter|last4=Haché|first4=Samuel|last5=Fontaine|first5=Trish|last6=Bayne|first6=Erin M.|last7=Mazerolle|first7=Dan|date=2019|title=Estimating the conservation value of protected areas in Maritime Canada for two species at risk: the Olive-sided Flycatcher (Contopus cooperi) and Canada Warbler (Cardellina canadensis)|url=http://www.ace-eco.org/vol14/iss1/art16/|journal=Avian Conservation and Ecology|language=en|volume=14|issue=1|pages=art16|doi=10.5751/ACE-01359-140116|issn=1712-6568|doi-access=free}} This study helped quantify the importance of protected areas for the species.

The loss of wintering habitat might be one of the main causes for its population decline. However, they do not seem to be directly impacted by forest loss, although they might be sensitive to it. Declines in flying insect populations due to insecticide use is thought to impact most directly the species. In their non-breeding habitat, on the east slope of Andes, winter populations are highly threatened, but the exact threats have not yet been identified. Burned or freshly logged forests are suitable foraging habitats for olive-sided flycatchers due to the increased presence of flying insects, but they could be negatively affected in these environments by wildfire suppression techniques or salvage logging. Collisions with communication towers seem to be another cause of mortality threatening olive-sided flycatchers.{{Cite journal|last1=Longcore|first1=Travis|last2=Rich|first2=Catherine|last3=Mineau|first3=Pierre|last4=MacDonald|first4=Beau|last5=Bert|first5=Daniel|last6=Sullivan|first6=Lauren|last7=Mutrie|first7=Erin|last8=Gauthreaux|first8=Sidney|last9=Avery|first9=Michael|last10=Crawford|first10=Robert|last11=Manville|first11=Albert|date=2013|title=Avian mortality at communication towers in the United States and Canada: which species, how many, and where?|url=https://digitalcommons.unl.edu/icwdm_usdanwrc/1162|journal=USDA Wildlife Services - Staff Publications}}

• Willis, E.O.; Snow, D.W.; Stotz, D.F. & Parker III, T.A. (1993) Olive-sided Flycatchers in Southeastern Brazil Wilson Bulletin 105(1):

{{Commons|Contopus cooperi}}

{{Wikispecies|Contopus cooperi}}

• [http://www.mbr-pwrc.usgs.gov/id/framlst/i4590id.html Olive-sided flycatcher - Contopus cooperi] – USGS Patuxent Bird Identification InfoCenter
• [https://www.allaboutbirds.org/guide/Olive-sided_Flycatcher/id Olive-sided flycatcher species account] – Cornell Lab of Ornithology
• [https://www.youtube.com/watch?v=j_ITiAs9DfI Olive-sided flycatcher song]
• [https://merlin.allaboutbirds.org/ Merlin Bird ID – The Cornell Lab of Ornithology]
• [https://ebird.org/species/olsfly eBird olive-sided flycatcher ID]
• [https://www.youtube.com/watch?v=dneyIaqK2uE Olive-sided flycatcher eating a bee]

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olive-sided flycatcher

Category:Birds of North America

olive-sided flycatcher