Red howler monkeys. Photo by Sam Abell, 2010.

The Amazon rainforest contains a large portion of the world’s mammal species. To date, 427 mammals species have been documented in the Amazon [1], though this number is likely to increase as scientific expeditions record new species. According to Patterson [2], one new genus and eight new species of Neotropical mammals are discovered each year. Most of the mammalian species in the Amazon are rodents and bats, but there are also more unusual species, including swimming mammals like the Tapir (Tapirus terrestris), Giant otter (Pteronura brasiliensis) and the pink river dolphin (Inia geoffrensis; see Freshwater Species).

The most threatened mammal species in the Amazon are the primates. More than 100 species of primates are found within Brazil [3], many of which are found nowhere else in the world. Primates in the Amazon exist in many forms, from long-limbed spider and wooly monkeys, to smaller capuchin and squirrel monkeys, as well as marmosets and tamarins. Primates help to maintain biological diversity by serving as pollinators and seed dispersers within the tropical rainforest. A single spider monkey can disperse over 195,000 seeds over the course of one year [4], greatly contributing to rainforest regeneration. Of the 199 taxa of primates in the Neotropics, however, 35% are listed as threatened by the International Union for the Conservation of Nature (IUCN).

Mammals often traverse large habitat ranges, providing a buffer from small-scale habitat destruction. However, habitat fragmentation can disrupt migratory pathways in the Amazon, stressing populations of migrating mammals. Over the next several decades, forest cover in the Amazon is predicted to decrease by as much as 50% [7], threatening many of the region’s mammal species. While large conservation areas such as parks and concessions are critical in establishing and maintaining mammal habitat, migratory corridors are also important to allow unrestricted movement between mammal populations to maintain genetic diversity. Infrastructure projects such as the Interoceanic Highway obstruct such corridors, while conservation organizations work to mitigate impacts of roadways on mammal populations.

A family of capybaras. Photo by Sam Abell, 2010.

The Jaguar is easily one of the Amazon’s most recognized species. The largest felid in South America, the jaguar helps regulate prey population sizes [5]. It can weigh up to 300 pounds and has one of the strongest bites of any cat species on the planet, capable of crushing armadillo armor. Despite its large range throughout South America, the jaguar is listed by the IUCN as ‘Near Threatened’ due to hunting pressure imposed by farmers and ranchers throughout the Amazon. This top predator faces decline as food sources become restricted by habitat fragmentation and human encroachment [6].

  1.     World Wildlife Fund. (2010). Amazon Alive: A Decade of Discovery 1999-2009.
  2.     Patterson, B. D. (2000). Patterns and trends in the discovery of new Neotropical mammals. Diversity and Distributions6, 145-151.
  3.     Costa, L. P., Leite, Y. L. R., Mendes, S. L. and Ditchfield, A. D. (2005). Mammal Conservation in Brazil. Conservation Biology19(3), 672-679.
  4.     Link, A., and Di Fiore, A. (2006). Seed dispersal by spider monkeys and its importance in the maintenance of Neotropical rainforest diversity. Journal of Tropical Ecology22, 235-246.
  5.     Soisalo, M. K., and Cavalcanti, S. M. C. (2006). Estimating the density of a jaguar population in the Brazilian Pantanal using camera-traps, and capture-recapture sampling in combination with GPS radio-telemetry. Biological Conservation129, 487-496.
  6.     Nunez, R., Miller, B., and Lindzey, F. (2000). Food habits of jaguars and pumas in Jalisco, Mexico. Journal of Zoology,
  7. 252, 373-379.
  8.    Laurance, W. F., et al. (2001). The future of the Brazilian Amazon. Science291, 438-439.

Learn more about Mammals of the Amazon

All About Agoutis

Species Description Agoutis are rodents in the genus Dasyprocta, which consists of 12 known species found throughout Central and South America. These small mammals may grow up to 2.5 feet long and weigh up to 13 pounds [1]. Their fur comes in many shades of orange,...

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Incredible Wildlife Footage from the Peruvian Amazon

Of the Earth's 10 million species of plants and animals, almost one-third call the Amazon rainforest home. A single tree in Peru was found to have 43 different species of ants, a total that approximates the number of ant species found in the entire United Kingdom....

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Rare Amazon Jungle Dog Caught on Video

The Amazon jungle dog, Atelocynus microtis, is one of the forest’s most elusive animals. The short-eared dog is timid, about the size of a fox, and has a dark coloring that helps it hide from predators in the underbrush of the forest. They are so difficult to spot...

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Brazil plans to stop the killing of pink dolphins

SAO PAULO — Brazil will temporarily ban the catch of a type of catfish in an effort to halt the killing of the Amazon pink dolphin, whose flesh is used as bait, the Fishing and Aquaculture Ministry said Tuesday. Ministry spokesman Ultimo Valadares said the government...

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Ecuador’s Jaguars Threatened by Oil Drilling

Ecuador’s Yasuni National Park is one of the most biodiverse places on Earth. One hectare in Yasuni contains more tree species than are native to all of North America. The park contains countless bird species, frogs, eagles, monkeys, ocelots, and of course, jaguars....

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Animal Symphony at Yasuni National Park

Over the past two years, the video camera trap program at Yasuni National Park in the Ecuadorean Amazon has managed to capture amazing footage of animals rarely seen by humans. These cameras were primarily arranged around salt licks, where mammals, birds, and even...

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New Mammal Species Discovered in Andean Cloud Forests

Deep in the Andean cloud forests of Ecuador and Colombia, thousands of furry, raccoon-like mammals have managed to evade researchers for all of modern history. That is, until now. In August 2013, Kristofer Helgen--curator of mammals at the Smithsonian National Museum...

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Primates of the Amazon Rainforest

The most threatened mammal species in the Amazon are the primates, of which the Amazon is one of the most important regions for these mammals. More than 100 species of primates can be found within Brazil, many of which are found nowhere else in the world. [1] Primates...

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Squirrel Monkey

Squirrel monkeys live communally in large groups within the rainforest canopy. They have distinct vocalizations, some of which warn the group about specific threats including falcons and snakes. http://youtu.be/3zXGU4sELdw

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