CreatureData

Giant otter

Pteronura brasiliensis (Zimmermann, 1780)

ENEndangeredmammals

The giant otter (Pteronura brasiliensis), also called the Giant Brazilian otter, is a mammal in the family Mustelidae and subfamily Lutrinae, within the order Carnivora. Gestation lasts from 65 to 69 days, litters have up to 2 young, there is 1 litter per year, and sexual maturity is reached at 2 years.

Giant otter (Pteronura brasiliensis)
Photo: Giles Laurent · CC BY-SA 4.0 · Wikimedia Commons

Quick facts about the giant otter

The giant otter is listed as Endangered (EN) on the IUCN Red List, a threatened category.

Weight
22 kg – 32 kgsrc for Weight
Length
up to 1.8 msrc for Length
Lifespan
13.7 yearssrc for Lifespan
Diet
Piscivoresrc for Diet
Longest recorded lifespan
17.3 years
Main food
Not recorded
Habitat
freshwater, riverinesrc for Habitat
Gestation
65 days – 69 dayssrc for Gestation
Young per litter or clutch
1.94 – 2src for Young per litter or clutch
Age at maturity
2 yearssrc for Age at maturity
Litters or clutches a year
1src for Litters or clutches a year
Active
By day (diurnal)src for Active
Lifestyle
Terrestrialsrc for Lifestyle
Conservation status
Endangered (IUCN)src for Conservation status
Countries on record
Not recorded

Photos of the giant otter

Only freely licensed photos are shown. Each carries its creator and licence.

Giant otter (Pteronura brasiliensis)
Giles Laurent · CC BY-SA 4.0 · Wikimedia Commons
Giant otter (Pteronura brasiliensis)
Thomas Fuhrmann · CC BY-SA 4.0 · Wikimedia Commons
Giant otter (Pteronura brasiliensis)
Giles Laurent · CC BY-SA 4.0 · Wikimedia Commons
Giant otter (Pteronura brasiliensis)
Silvaninha2542 · CC BY-SA 4.0 · Wikimedia Commons
Giant otter (Pteronura brasiliensis)
DouglasFischer1969 · CC BY-SA 4.0 · Wikimedia Commons
Giant otter (Pteronura brasiliensis)
BluesyPete · CC BY-SA 3.0 · Wikimedia Commons
Giant otter (Pteronura brasiliensis)
BluesyPete · CC BY-SA 3.0 · Wikimedia Commons

1 more photo exists under a licence we cannot display: view at source.

Where does the giant otter live?

Not recorded

What is the giant otter?

Quoted from WikipediaCC BY-SA 4.0

The giant otter or giant river otter (Pteronura brasiliensis) is a South American carnivorous mammal. It is the longest member of the weasel family, Mustelidae, reaching up to 1.8 m (5 ft 11 in). Atypical of mustelids, the giant otter is a social species, with family groups typically supporting three to eight members. The groups are centered on a dominant breeding pair and are extremely cohesive and cooperative. Although generally peaceful, the species is territorial and aggression has been observed between groups. The giant otter is diurnal, being active exclusively during daylight hours. It is the noisiest otter species and distinct vocalizations have been documented that indicate alarm, aggression and reassurance.

The giant otter ranges across north-central South America; it lives mostly in and along the Amazon River and in the Pantanal. Its distribution has been greatly reduced and is now discontinuous. Decades of poaching for its velvety pelt, peaking in the 1950s and 1960s, considerably diminished population numbers. The species was listed as endangered in 1999 and wild population estimates are typically below 5,000. The Guianas are one of the last real strongholds for the species, which also enjoys modest numbers – and significant protection – in the Peruvian Amazonian basin. It is one of the most endangered mammal species in the Neotropics. Habitat degradation and loss is the greatest current threat. They are also rare in captivity; in 2003, only 60 giant otters were being held.

The giant otter shows a variety of adaptations suitable to an amphibious lifestyle, including exceptionally dense fur, a wing-like tail, and webbed feet. The species prefers freshwater rivers and streams, which are usually seasonally flooded, and may also take to freshwater lakes and springs. It constructs extensive campsites close to feeding areas, clearing large amounts of vegetation. The giant otter subsists almost exclusively on a diet of fish, particularly characins and catfish, but may also eat crabs, turtles, snakes and small caimans. It has no serious natural predators other than humans, although it must compete with other predators, such as the Neotropical otters and various crocodilian species, for food resources.

From the Wikipedia article “Giant otter” (en.wikipedia.org/w/index.php?title=Giant_otter&oldid=1383833140), by Wikipedia contributors, licensed under CC BY-SA 4.0 (creativecommons.org/licenses/by-sa/4.0). This block is kept separate from our own text.

Is the giant otter endangered?

The giant otter is listed as Endangered on the IUCN Red List: it faces a very high risk of extinction in the wild.

  1. LCLeast Concern
  2. NTNear Threatened
  3. VUVulnerable
  4. ENEndangered
  5. CRCritically Endangered
  6. EWExtinct in the Wild
  7. EXExtinct

Category via Wikidata (CC0). Find the full assessment on the IUCN Red List. See all Endangered species.

How is the giant otter classified?

  1. kingdomAnimalia
  2. phylumChordata
  3. classMammalia
  4. orderCarnivora
  5. familyMustelidae
  6. genusPteronura
  7. SpeciesPteronura brasiliensis (Zimmermann, 1780)

Synonyms Lutra brasiliana, Lutra brasiliensis, Lutra brasiliensis, Lutra lupina, Lutra paraguensis, Lutra paranensis, Mustela brasiliensis, Mustela brasilinensis, Mustela lutris brasiliensis, Pteronura brasiliensis, Pteronura brasiliensis brasiliensis, Pteronura brasiliensis paraguensis, Pteronura brasiliensis paranensis, Pteronura sambachii, Pterura sanbachii

Other names and names in other languages (1)
  • Giant Brazilian otterEnglish

Catalogue of LifeWikipediaWikidataIUCN Red List

Relatives of the giant otter

Other species in the same family Mustelidae.

LC, Least Concern
Stoat (Mustela erminea)

Stoat

Mustela erminea

Mustelidae

LC, Least Concern
Wolverine (Gulo gulo)

Wolverine

Gulo gulo

Mustelidae

CompareGiant otter vs European badgerGiant otter vs Least weaselGiant otter vs Eurasian otterGiant otter vs Stoat

Common questions

Each answer is written from the sourced facts on this page, and only where they hold the answer.

What kind of animal is the giant otter?

The giant otter is a mammal in the family Mustelidae, subfamily Lutrinae, in the order Carnivora.

How heavy is a giant otter?

Adult giant otters weigh from 22 to 32 kg, with a representative value of 24 kg.

What does the giant otter eat?

The giant otter is a piscivore, and its trophic level is carnivore.

Is the giant otter endangered?

Yes. The giant otter is listed as Endangered (EN) on the IUCN Red List, which is a threatened category.

How long does a giant otter live?

The giant otter has a lifespan of 13.67 years, with values up to 17.3 years reported.

How many young does a giant otter have?

Giant otters have up to 2 young per litter, with 1 litter per year, after a gestation of 65 to 69 days.

Sources and how to cite this page

Data as of 2026-11-11. How this page is put together.

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APA

CreatureData. (2026). Giant otter (Pteronura brasiliensis). Retrieved from https://creaturedata.com/animals/giant-otter

MLA

“Giant otter (Pteronura brasiliensis).” CreatureData, 2026, https://creaturedata.com/animals/giant-otter.

BibTeX
@misc{giant_otter_2026,
  title = {Giant otter (Pteronura brasiliensis)},
  author = {{CreatureData}},
  year = {2026},
  url = {https://creaturedata.com/animals/giant-otter},
  note = {Data as of 2026-11-11}
}