Molothrus oryzivorus
Silhouette: Andy Wilson · PhyloPic
In 3 days ~70% in a week ~90%
The giant cowbird (Molothrus oryzivorus) is a large passerine bird in the New World family Icteridae. It breeds from southern Mexico south to northern Argentina, and on Trinidad and Tobago. It may have relatively recently colonised the latter island. It is a brood parasite and lays its eggs in the nests of other birds.
The giant cowbird was formally described in 1788 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae. He placed it with the orioles in the genus Oriolus and coined the binomial name Oriolus oryzivorus. Gmelin based his account on the "rice bird" from Cayenne that had been described in 1782 by the English ornithologist John Latham in his multi-volume work A General Synopsis of Birds. The specific epithet is from Latin oryza meaning "rice" and -vorus meaning "eating". The giant cowbird is now one of six cowbirds placed in the genus Molothrus that was introduced in 1832 by William Swainson.
Two subspecies are recognised: Wikipedia →
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Santa Cruz de la Sierra | 🇧🇴 Bolivia | |
| 2 | Belém | 🇧🇷 Brazil | |
| 3 | Guayaquil | 🇪🇨 Ecuador | |
| 4 | Barranquilla | 🇨🇴 Colombia | |
| 5 | San Pedro Sula | 🇭🇳 Honduras | |
| 6 | Medellín | 🇨🇴 Colombia | |
| 7 | San José | 🇨🇷 Costa Rica | |
| 8 | Caracas | 🇻🇪 Venezuela | |
| 9 | Panama City | 🇵🇦 Panama | |
| 10 | Bogota | 🇨🇴 Colombia |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Parque das Aves | 🇧🇷 Brazil |
Possible
About 30% of wildlife watchers report a Giant Cowbird sighting in Amboró National Park on a given day, based on 180 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 43rd most-seen of the 273 birds we can rate there. Over three days the chance rises to about 70%, and over a week to about 90%, if each day is a fresh chance.
September–October and December
In those months about 50% of wildlife watchers report a Giant Cowbird in Amboró National Park on a given day, against about 10% in April–May and July–August, the lowest months. June has too few records to rate.
Between 7 and 10 am
Across all the parks we cover, that three-hour window holds the most Giant 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 50 parks where we can rate Giant Cowbird sightings, Amboró National Park has the highest daily chance: about 30%. Next come Main Ridge Forest Reserve (Trinidad and Tobago, about 30%) and Yasuní National Park (Ecuador, about 20%).
Same family: Icteridae
The closest relatives of the Giant Cowbird that you can see in Amboró National Park (family Icteridae, New World Blackbirds and Orioles) are Crested Oropendola (about 80%) and Dusky-green Oropendola (about 60%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Giant Cowbird is recorded against all the birds logged in Amboró National Park (180 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.
