Empidonax traillii
Silhouette: Emily Willoughby · PhyloPic
In 3 days ~10% in a week ~20%
The willow flycatcher (Empidonax traillii) is a small insect-eating, migrant bird of the tyrant flycatcher family native to North America. The willow flycatcher was included by the Franco-American ornithologist John James Audubon in his book The Birds of America based on a specimen collected in the "woods along the prairie banks of the Arkansas River". The section of the book containing the willow flycatcher was published in 1828. There are two variants of the plate illustrating the flycatcher. On one the binomial name is given as Muscicapa trailli and on the other as Muscicapa traillii. The latter spelling was used in 1831 by Audubon when describing the species in his Ornithological Biography that was published to accompany the plates and is now the accepted spelling. The specific epithet was chosen by Audubon to honour his friend the Scottish physician and zoologist Thomas Stewart Traill. The willow flycatcher is now one of 14 species placed in the genus Empidonax that was introduced in 1855 by the German ornithologist Jean Cabanis.
There are four subspecies recognized, all of which breed in North America (including three subspecies that breed in California). At one... Wikipedia →
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Vancouver | 🇨🇦 Canada | |
| 2 | Seattle | 🇺🇸 United States | |
| 3 | Chicago | 🇺🇸 United States | |
| 4 | New York City | 🇺🇸 United States | |
| 5 | Portland | 🇺🇸 United States | |
| 6 | Toronto | 🇨🇦 Canada | |
| 7 | Baltimore | 🇺🇸 United States | |
| 8 | Boston | 🇺🇸 United States | |
| 9 | Philadelphia | 🇺🇸 United States | |
| 10 | San Pedro Sula | 🇭🇳 Honduras |
Rare
Under 5% of wildlife watchers report a Willow Flycatcher sighting in Yellowstone National Park on a given day, based on 117 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 120th most-seen of the 197 birds we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
Any time of year
In every month with enough records, under 5% of wildlife watchers report a Willow Flycatcher in Yellowstone National Park on a given day, so our monthly data shows no clear season.
Between 8 and 11 am
Across all the parks we cover, that three-hour window holds the most Willow Flycatcher sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
9th of 42
Of the 42 parks where we can rate Willow Flycatcher sightings, Yellowstone National Park ranks 9th at under 5%. The best odds are in Glacier National Park (United States, about 20%), Banff National Park (Canada, about 10%) and Grand Teton National Park (United States, about 10%).
Same genus: Empidonax
The closest relatives of the Willow Flycatcher that you can see in Yellowstone National Park (genus Empidonax, Empidonax Flycatchers) are Hammond's Flycatcher (about 10%) and Dusky Flycatcher (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Willow Flycatcher is recorded against all the birds logged in Yellowstone National Park (117 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
