Amazonian Manatee

The Amazonian Manatee is considered a Vulnerable species by the IUCN.


  • Kingdom: Animalia
  • Phyllum: Chordata
  • Class: Mammalia
  • Order: Sirenia
  • Family: Trichechidae
  • Genus: Trichechus
  • Species: Trichechus inunguis




  • Common name: Amazonian manatee, South American manatee, Amazon sea cow.
  • Scientific name: Trichechus inunguis.

Physical Features

  • The Amazonian manatee is the smallest of the three living species of the Trichechus genus, the West Indian manatee (trichechus manatus) and the West African manatee (Trichechus senegalensis).
  • Its skin color is gray with white markings on the abdomen and chest. Its rubbery skin is 2 inches thick (5 cm) and covered with fine hairs.
  • They have thick bristles on the upper and lower lips.
  • The Amazonian manatee has elongated flippers and lack nails. These are the main characteristics that differentiate the Amazonian manatee from the West Indian and West African manatees.
  • Manatees have 6 neck vertebrae, all other mammals have 7.

Distribution and Habitat

  • Amazonian manatees are distributed throughout the Amazon Basin covering an area of approximately 2.7 million sq miles (7 million sq km) in Brazil, Bolivia, Colombia, Ecuador and Peru.
  • Their habitat includes the murky waters of rivers and lagoons and nutrient rich flooded forests.
  • It is the only manatee that occurs exclusively in freshwater.
Amazonian Manatee Distribution Map

Amazonian Manatee Distribution Map.


  • Manatees are very secretive and shy.
  • They are both diurnal and nocturnal.
  • During the rainy season they migrate to flooded areas and during the dry season to deeper bodies of water.
  • They live in groups of 4 to 8 individuals.
  • Females carry the young on their backs or clasped to their side.
  • They eat mostly during the wet season. During the dry season they may not eat as much.
  • Manatees never leave the water but have to swim to the surface to breath air.
  • They are slow swimmers which makes them easy prey for hunters. They move at 5 mph (8 km/h) but can swim as fast as 15 mph (24 km/h) in short bursts.

Size and Weight

  • The largest recorded Amazonian manatee was 9.2 feet (2.8 meters).
  • The heaviest recorded was 836.5 lb (379.5 kg).


  • Amazonian manatees breed throughout the year.
  • In captivity they reach reproductive maturity at 2.5 years. It is unknown in the wild.
  • Gestation period is 12 months and females give birth to one calf.
  • Birth interval is 2 to 3 years.
  • Manatees are born underwater, right after birth the mother has to push her newborn to the surface to breathe.


  • This mammal is herbivorous and eats aquatic, semi aquatic plants and fallen fruit.
  • They eat up to 8% of their body weight a day.

Life Expectancy

  • An Amazonian manatee is expected to live an average of 12 years in captivity.
  • Its life expectancy in the wild is unknown.


  • Humans, jaguars, crocodiles.


  • The IUCN predicts a population decline of at least 30% over the next 60 years.
  • The Amazonian manatee has long been hunted by indigenous people for its meat and hide.
  • Low birth rate, high calf mortality, climate change and habitat loss and degradation.

Conservation Status

IUCN Vulnerable

  • Trichechus inunguis is listed as Vulnerable by the IUCN Red List of Threatened Species.
  • It is listed on Appendix I of CITES.

Did you know?

  • Mixira is a popular dish in the Amazon and its main ingredient is manatee meat.



References and further research

IUCN Sirenia Speciealist Group

IUCN Red List of Threatened Species – Trichechus inunguis

American Society of Mammalogy – Trichechus inunguis

World Register of Marine Species

ITIS Report – Trichechus inunguis

Marine Species Identification Portal

University of Michigan Museum of Zoology – Trichechus inunguis

Google Scholar