Empidonax difficilis
Silhouette: Emily Willoughby · PhyloPic
In 3 days ~30% in a week ~60%
The western flycatcher (Empidonax difficilis) is a small insectivorous bird in the family Tyrannidae. It is native to western North America, where it breeds in the Rocky Mountains and Pacific Coast forests and mountain ranges from California to Alaska and south to central Mexico; northern populations migrate south to Mexico for the winter.
The western flycatcher was recognized as a single species until 1989, when the American Ornithologists' Union split it into two different species: the Pacific-slope flycatcher (E. difficilis) of coastal western North America and parts of the western Rocky Mountains, and the Cordilleran flycatcher (E. occidentalis) of the interior Rocky Mountains, with both species wintering in Mexico. Both species looked virtually identical to one another, with the split being based on differing breeding habitats and apparent differences in songs and calls. The split was recognized until 2023, when the American Ornithologists' Union and International Ornithological Congress again lumped both species due to a lack of consistent vocal, genetic, morphological differences and extensive hybridization across much of their range.
There are... Wikipedia →
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Tijuana | 🇲🇽 México | |
| 2 | Vancouver | 🇨🇦 Canada | |
| 3 | San Diego | 🇺🇸 United States | |
| 4 | Toluca | 🇲🇽 México | |
| 5 | Los Angeles | 🇺🇸 United States | |
| 6 | San Francisco | 🇺🇸 United States | |
| 7 | Seattle | 🇺🇸 United States | |
| 8 | Guadalajara | 🇲🇽 México | |
| 9 | Portland | 🇺🇸 United States | |
| 10 | Mexico City | 🇲🇽 México |
With luck
About 10% of wildlife watchers report a Pacific-slope Flycatcher sighting in San Diego on a given day, based on 5,683 verified sightings from GBIF citizen-science data. It is the 67th most-seen of the 386 birds we can rate there. Over three days the chance rises to about 30%, and over a week to about 60%, if each day is a fresh chance.
May and June
In those months about 40% of wildlife watchers report a Pacific-slope Flycatcher in San Diego on a given day, against under 5% in October to February, the lowest months. Those are among San Diego's driest months, with about 10 mm of rain a month against 55 mm in February.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Pacific-slope 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.
3rd of 21
Of the 21 cities where we can rate Pacific-slope Flycatcher sightings, San Diego ranks 3rd at about 10%. The best odds are in Tijuana (México, about 30%) and Vancouver (Canada, about 10%).
GBIF citizen-science records
It is estimated from how often the Pacific-slope Flycatcher is recorded against all the birds logged in San Diego (5,683 verified sightings), 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.
