promoções ecologicamente


Giant Otter (Pteronura brasiliensis)

  • Giant Otter (Pteronura brasiliensis)

    Common Name/s: Giant Otter 
    Scientific name: Pteronura brasiliensis
    Brazilian common name/s: Ariranha

    Quick facts (average values with minimum and maximum in parenthesis)

    Body length (cm): (100-120)a,b  Tail (cm):  (53-70) a,b Diet: Carnivorous
    Weight (kg): (22-34) a,b Height (cm):  Home range (km2): (12-40)b
    Litter size: 2 (1-5) b Gestation (days): (52-70) b Longevity (years): 
    Social structure:
     Groups a,b
    Activity pattern: Diurnala,b

    a (Emmons & Feer 1997), b (Carter & Rosas 1997)

    Physical description
    One of the largest carnivores in South America, and the largest of all otters. Similar to the neotropical otter, but is larger, has white spots on its throat and the terminal portion of the tail is flattened. The coat is short with a brown coloration. The feet are broad, with webbed toes.

    Habitat and Ecology
    They occur in South America, from the east of Ecuador and Peru to northern Argentina and are mainly found in forests or wetlands with slow moving rivers. They are active during the day and spend most of the time in the water.
    They have an interesting social system, with groups of 4 to 8 individuals, comprising a monogamous breeding pair and their offspring (Carter & Rosas 1997); (Leuchtenberger & Mourao 2008).
    The diet consists mainly of fish, crabs and occasionally other small vertebrates. The prey is captured with the mouth and secured with the paws to be consumed, often while the animal swims on its back (Cabral et al. 2010; Carter et al. 1999; Rosas et al. 1999).

    Threats and Conservation
    Their populations have been greatly reduced due to hunting for their fur, however at least some protected populations are recovering (Uscamaita & Bodmer 2010). Main threats are: habitat destruction and associated water pollution by pesticides, industrial waste and mercury (Carter & Rosas 1997; Duplaix et al. 2008). Loss of forest habitat significantly influences their probability of occurrence (Michalski & Peres 2005) and it is estimated that habitat loss will cause population declines of 50% in 20 years (Duplaix et al. 2008). It is classified by the IUCN (International Union for Conservation of Nature) as Endangered and by IBAMA, as threatened with extinction.

    Online links
    IUCN redlist ( presents a summary of current knowledge on distribution and conservation status

    IUCN Otter Specialist Group -

    The world"s chief body of scientific and practical expertise on the status and conservation of all otter species

    IUCN OSG Bulletin –

    Free online peer reviewed publications published by the IUCN Otter Specialist Group

    Cabral, M. M. M., Zuanon, J., de Mattos, G. E., & Rosas, F. C. W. (2010). Feeding habits of giant otters Pteronura brasiliensis (Carnivora: Mustelidae) in the Balbina hydroelectric reservoir, Central Brazilian Amazon. Zoologia, 27, 47-53.

    Carter, S. K., & Rosas, F. C. W. (1997). Biology and conservation of the giant otter Pteronura brasiliensis. Mammal Review, 27, 1-26.

    Carter, S. K., Fernando, C. W., Copper, A. B., & Cordeiro-Duarte, A. C. (1999). Consumption rate, food preferences and transit time of captive giant otters Pteronura brasiliensis: Implications for the study of wild populations. Aquatic mammals, 25, 79-90.

    Duplaix, N., Waldemarin, H. F., Groenedijk, J., Evangelista, E., Munis, M., Valesco, M., & Botello, J. C. (2008). Pteronura brasiliensis. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.2.. <>, , Downloaded on 05 July 2010.

    Emmons, L. H., & Feer, F. (1997). Neotropical rainforest mammals: a field guide. Chicago: University of Chicago Press.

    Leuchtenberger, C., & Mourao, G. (2008). Social organization and territoriality of giant otters (Carnivora : Mustelidae) in a seasonally flooded savanna in Brazil. Sociobiology, 52, 257-270.

    Michalski, F., & Peres, C. A. (2005). Anthropogenic determinants of primate and carnivore local extinctions in a fragmented forest landscape of southern Amazonia. Biological Conservation, 124, 383-396.

    Rosas, F. C. W., Zuanon, J. A. S., & Carter, S. K. (1999). Feeding ecology of the giant otter, Pteronura brasiliensis. Biotropica, 31, 502-506.

    Uscamaita, M. R., & Bodmer, R. (2010). Recovery of the Endangered giant otter Pteronura brasiliensis on the Yavari-Mirin and Yavari Rivers: a success story for CITES. Oryx, 44, 83-88.

< back
Adress Horacio Neto, 1030 Park House 10 Edmundo Zanoni Atibaia - SP - 12945-010, Brazil.Phone: (+55) 11 44116966