Alouatta guariba
Silhouette: PhyloPic
In 3 days ~20% in a week ~30%
The brown howler (Alouatta guariba), also known as brown howler monkey, is a species of howler monkey, a type of New World monkey that lives in forests in south-eastern Brazil and far north-eastern Argentina (Misiones). It lives in groups of two to 11 individuals. Despite the name "brown howler", it is notably variable in colour, with some individuals appearing largely reddish-orange or black.
The two subspecies are: Northern brown howler (A. g. guariba), listed as critically endangered Southern brown howler (A. g. clamitans) The brown howler is found in the Atlantic forest of South America. The region spreads through the Brazilian states of Bahia and Espírito Santo through Rio Grande do Sul, and Misiones in Argentina.
Brown howler monkeys are folivores and frugivorous. The diet of the brown howler monkey consists primarily of leaves and trees. Of the food sources it seems that the genera Ficus, Zanthoxylum, and Eugenia are the most significant types consumed. Brown howler monkeys that live in higher latitudes tend to eat a lower percentage of leaves in their diet. Mature leaves are less nutritious and are more fibrous, than the preferred young leaves.... Wikipedia →
Recording0:14
Brazil · 2019
© amandapmarcon · iNaturalist · CC BY-NC 4.0
Recording0:52
Brazil · 2025
Paula Romano · iNaturalist · CC0
Recording1:11
Brazil · 2022
© lucasforti · iNaturalist · CC BY-NC 4.0
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Tijuca National Park | 🇧🇷 Brazil |
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | São Paulo | 🇧🇷 Brazil |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Denver Zoo | 🇺🇸 United States | |
| 2 | Zoológico de Brasília | 🇧🇷 Brazil | |
| 3 | São Paulo Zoo | 🇧🇷 Brazil | |
| 4 | Zoológico Municipal de Cascavel | 🇧🇷 Brazil | |
| 5 | Parque Ecológico de São Carlos | 🇧🇷 Brazil | |
| 6 | Zoológico Municipal de Guarulhos | 🇧🇷 Brazil | |
| 7 | Parque Zoológico Bosque Guarani | 🇧🇷 Brazil | |
| 8 | Ecozoológico San Martín | 🇪🇨 Ecuador | |
| 9 | Parque Zoobotânico Orquidário Municipal de Santos | 🇧🇷 Brazil | |
| 10 | Arequipa zoo | 🇵🇪 Peru |
With luck
About 10% of wildlife watchers report a Brown Howler Monkey sighting in Tijuca National Park on a given day, based on 7 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 12th most-seen of the 14 mammals we can rate there. Over three days the chance rises to about 20%, and over a week to about 30%, if each day is a fresh chance.
April and December–February
In those months about 10% of wildlife watchers report a Brown Howler Monkey in Tijuca National Park on a given day, against under 5% in March and May–November, the lowest months.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Brown Howler Monkey sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Only Tijuca National Park, in our data
Tijuca National Park is the only park on Wallace's Line with enough records to rate Brown Howler Monkey sightings: about 10% of wildlife watchers there report one on a given day.
Same order: Primates
The closest relatives of the Brown Howler Monkey that you can see in Tijuca National Park (order Primates) are Mono Cai (about 40%), Common Marmoset (about 30%) and Black-pencilled Marmoset (about 30%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Brown Howler Monkey is recorded against all the mammals logged in Tijuca National Park (7 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.
