The Amazon - a tropical rainforest: fauna

Chapter summary

• There are over 300 species of mammals in the Amazon.
• Jaguars are the biggest cats in the Americas.
• Snakes, lizards and tortoises are common in the Amazon.
• Deforestation is a major problem in the Amazon rainforest.
• Many animals are hunted to the point of extinction or near extinction.

Animal life in the Amazon rainforest

There are over 300 species of mammals in the Amazon, with monkeys being the most common. The Amazon is also home to some unusual creatures.

Capybara

The capybara is the world's largest rodent and can weigh up to 110 kg. It looks like a very large guinea pig. It is a herbivore and grazes beside the river, where it also likes to swim. See video 1

Tapir

The tapir is about one metre tall and looks similar to a horse, with an elongated nose. Tapirs are timid, and move towards the water when disturbed.

Sloths

Sloths are related to anteaters. They have three toes. There are four distinct species of sloth in the Amazon. They move very slowly, so they are vulnerable when on the ground. They spend most of their time in trees.

Jaguars

Jaguars are the biggest cats in the Americas. They can grow up to two metres in length and an adult male can weigh 115kg. It is the predator at the top of the food chain, but is thought to be one of  the most endangered species in the rainforest. See image 1

Birds of the Amazon rainforest

The birdlife of the Amazon is very exotic with various colours and calls.

Macaws

Macaws are part of the parrot family. They nest in hollows in palm trees. Like most parrots, they are very noisy, especially at dawn and dusk, giving the rainforest its special sound. They are brightly coloured in red, emerald green, sapphire blue and gold. See image 2

Toucans

Toucans are known for their huge bills, which are brightly coloured and are often as long as their bodies. Toucans eat fruit, insects, and small animals, such as lizards. Their bills are made of a honeycomb type structure and are very light but also very strong. See image 3

Reptiles of the Amazon Rainforest

Snakes, lizards and tortoises are common in the Amazon.

Red-legged tortoises

Red-logged tortoises are endemic to the Amazon, where they make their damp, muddy dens and feed on the shaded forest floor and from the river. They are large, slow-moving creatures which live for a very long time: up to 200 years. Their shell, when fully grown, is approximately half a metre long.

Boa constrictors

Boa constrictors are very large, powerful snakes, which grow up to four metres in length. They prey on small mammals. They are not big enough to kill humans, so they are welcome around residential areas, where they help to limit the rodent population. Boa constrictors kill their prey by suffocation. They wind their bodies around their prey, squeeze it to death and then swallow it whole. Boa constrictors live in the canopy of the rainforest, as well as on the forest floor.

Anaconda

The anaconda is thought to be the largest snake in the world, reaching a length of ten metres and weighing up to 225kg. Anacondas are large enough to attack humans. See image 4

Black caiman

The black caiman is a type of alligator. It is the largest caiman in the Americas and grows up to five metres long. It feeds on birds and small mammals, as well as other reptiles and fish. 

The river inhabitants

The Amazon rainforest developed because of the Amazon river and its tributaries. It is, therefore, also important to look at the inhabitants of the river.

Piranhas

Piranhas have sharp teeth and are carnivorous. They eat meat, and can taste blood in the water. They normally swim alone and feed on smaller fish or seeds in the water, but can sometimes swim in groups to attack a larger animal. See image 5

Boto

The boto is the Amazon River dolphin, also called the pink dolphin. The boto is a freshwater dolphin that can grow up to 2.5 metres long and can weigh up to 50kg. They swim along the bottom of the river, searching for fish and crustaceans. They stun their prey by bombarding them with high-frequency sound waves. Their sonar sensory equipment is located in the bulge on their foreheads.

Another dolphin found in the Amazon is the grey dolphin. It is smaller than the pink dolphin and much more agile. It tends to chase and catch fish near the surface.

Amazonian manatee

These large creatures can weigh up to 500kg. They breathe air via their nostrils, breaking the surface of the water to breathe as they cruise slowly along the top of the river. They feed on plants such as grasses and weeds. See image 6

Problems in the Amazonian rainforest

Problems in the Amazon began in the 1960s, when the Brazilian government started to open up the Amazon region by building roads. It is estimated that 80 percent of Amazonian deforestation has been caused by road building. The Brazilian government also encouraged people to cut down the forest for cattle ranches and farms. In the late 1990s, China became a large importer of soy. Brazil responded by planting more soy, which contributes to Amazon deforestation. The Amazon soil is so poor that it can only support a small number of crops before it becomes exhausted and cannot grow anything at all. Farmers, therefore, have to cut down more rainforest to clear areas for new farms. See image 7

The rainforest timbers are also used as building materials. This is causing many of the huge rainforest trees, some of which have taken 800 years to grow, to become endangered. This practice is not sustainable. Once cut down, these trees cannot be regrown because the environment has been altered.

As the number of trees in the rainforest decreases, so does the ecosystem that provides shelter and food for its animals. Many animals are hunted for food to the point of extinction or near extinction. The jaguar and the manatee are just two of the rainforest animals that are now on the list of endangered species.

The macaw (see video 2) and the woolly monkey are examples of animals suffering as a result of illegal international trade in endangered species.