Molothrus rufoaxillaris
Silhouette: Andy Wilson · PhyloPic
In 3 days ~30% in a week ~50%
The screaming cowbird (Molothrus rufoaxillaris) is an obligate brood parasite belonging to the family Icteridae and is found in South America. It is also known commonly as the short billed cowbird. The screaming cowbird has mildly iridescent black plumage; the lesser under-wing coverts are rufous. The female is slightly duller in colour than the male. The legs are black and the iris is reddish brown. Adult body length is 18–21 cm and mean adult weight is 58 g for males and 48 g for females. The call of the screaming cowbird was first described as "impetuous screaming notes"; however, a more useful description for field identification is noisy, explosive and piercing with rasp-like calls also produced. Screaming cowbirds are mostly seen in pairs or small flocks.
Within South America, the screaming cowbird is found in north east and central Argentina, south east Bolivia, central Brazil and throughout Paraguay and Uruguay. Its natural habitat is pastureland where it forages amongst grazing animals such as cows, hence the name "cowbird". Similar to other cowbirds, it forages predominantly on the ground, eating invertebrates that have been... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Iberá National Park | 🇦🇷 Argentina | |
| 2 | El Palmar National Park | 🇦🇷 Argentina | |
| 3 | Emas National Park | 🇧🇷 Brazil | |
| 4 | El Impenetrable National Park | 🇦🇷 Argentina | |
| 5 | Chapada dos Guimarães National Park | 🇧🇷 Brazil | |
| 6 | Serra da Canastra National Park | 🇧🇷 Brazil | |
| 7 | Iguaçu National Park | 🇧🇷 Brazil | |
| 8 | Iguazú National Park | 🇦🇷 Argentina |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Cordoba | 🇦🇷 Argentina | |
| 2 | Buenos Aires | 🇦🇷 Argentina | |
| 3 | Rosario | 🇦🇷 Argentina | |
| 4 | Mendoza | 🇦🇷 Argentina | |
| 5 | Montevideo | 🇺🇾 Uruguay | |
| 6 | Asuncion | 🇵🇾 Paraguay | |
| 7 | Santa Cruz de la Sierra | 🇧🇴 Bolivia | |
| 8 | Porto Alegre | 🇧🇷 Brazil | |
| 9 | Santiago | 🇨🇱 Chile | |
| 10 | Curitiba | 🇧🇷 Brazil |
With luck
About 10% of wildlife watchers report a Screaming Cowbird sighting in Iberá National Park on a given day, based on 151 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 154th most-seen of the 284 birds we can rate there. Over three days the chance rises to about 30%, and over a week to about 50%, if each day is a fresh chance.
November
In that month about 20% of wildlife watchers report a Screaming Cowbird in Iberá National Park on a given day, against under 5% in March, May and July, the lowest months.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Screaming Cowbird sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Yes
Of the 8 parks where we can rate Screaming Cowbird sightings, Iberá National Park has the highest daily chance: about 10%. Next come El Palmar National Park (Argentina, about 10%) and Emas National Park (Brazil, under 5%).
GBIF citizen-science records
It is estimated from how often the Screaming Cowbird is recorded against all the birds logged in Iberá National Park (151 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.
