Molothrus ater
Silhouette: Andy Wilson · PhyloPic
In 3 days ~30% in a week ~60%
The brown-headed cowbird (Molothrus ater) is a small, obligate brood parasitic icterid native to temperate and subtropical North America. It is a permanent resident in the southern parts of its range; northern birds migrate to the southern United States and Mexico in winter, returning to their summer habitat around March or April.
The brown-headed cowbird was described by the French polymath Georges-Louis Leclerc, Comte de Buffon in 1775 in his Histoire Naturelle des Oiseaux from a specimen collected in the Carolinas. The bird was also illustrated in a hand-colored plate engraved by François-Nicolas Martinet in the Planches Enluminées D'Histoire Naturelle, which was produced under the supervision of Edme-Louis Daubenton to accompany Buffon's text. Neither the plate caption nor Buffon's description included a scientific name, but in 1783, Dutch naturalist Pieter Boddaert coined the binomial name Oriolus ater in his catalogue of the Planches Enluminées. The brown-headed cowbird is now placed in the genus Molothrus that was introduced by English naturalist William Swainson in 1832 with the brown-headed cowbird as the type species. The genus name combines the Ancient Greek... Wikipedia →
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | León | 🇲🇽 México | |
| 2 | Detroit | 🇺🇸 United States | |
| 3 | Chicago | 🇺🇸 United States | |
| 4 | Baltimore | 🇺🇸 United States | |
| 5 | Washington | 🇺🇸 United States | |
| 6 | Mesa | 🇺🇸 United States | |
| 7 | Philadelphia | 🇺🇸 United States | |
| 8 | Toronto | 🇨🇦 Canada | |
| 9 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 10 | Dallas | 🇺🇸 United States |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Columbus Zoo and Aquarium | 🇺🇸 United States | |
| 2 | Omaha’s Henry Doorly Zoo and Aquarium | 🇺🇸 United States | |
| 3 | Ralph Perkins II Wildlife Center and Woods Garden | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Brown-headed Cowbird sighting in Portland on a given day, based on 5,484 verified sightings from GBIF citizen-science data. It is the 55th most-seen of the 230 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 Brown-headed Cowbird in Portland on a given day, against under 5% in September to March, the lowest months. Those are among Portland's driest months, with about 65 mm of rain a month against 250 mm in December.
Between 8 and 11 am
Across all the parks we cover, that three-hour window holds the most Brown-headed Cowbird sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
14th of 36
Of the 36 cities where we can rate Brown-headed Cowbird sightings, Portland ranks 14th at about 10%. The best odds are in León (México, about 30%), Detroit (United States, about 30%) and Chicago (United States, about 30%).
GBIF citizen-science records
It is estimated from how often the Brown-headed Cowbird is recorded against all the birds logged in Portland (5,484 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.
