Agonistic behavior between introduced beaver (Castor canadensis) and endemic culpeo fox (Pseudalopex culpaeus lycoides) in Tierra del Fuego Island and implications


Over the last 70 years, introduced beavers (Castor canadensis) have been successful in establishing and modifying the landscape of southernmost Patagonia. Habitat availability and lack of large carnivorous predators have contributed to this success. The Fuegian culpeo fox (Pseudalopex culpaeus lycoides) is an endangered subspecies and the largest native predator found in Tierra del Fuego Island. The predatory behavior of a culpeo towards a beaver was studied by analyzing a video footage recovered by tourists, and consumption of beaver was documented with camera traps. An ethogram of the predatory behavior sequence was developed and true durations and percentage of time allocated to each behavior were analyzed. The “capture” and “watch” behaviors had the highest durations within the predatory sequence (61.83 and 42.61 s, respectively), while “rest” was the most frequent maintenance behavior observed (93.82 s). The culpeo may provide the only natural population control for beavers, although up to date, there is no evidence to confirm this ecological role. Based upon photos from camera traps, we confirm the occurrence of fox feeding on beavers. This is the first description of the stages of the interaction between a Fuegian culpeo fox and a North American beaver under natural conditions. We discuss the ecological implications of this interaction.

This is a preview of subscription content, log in to check access.

Access options

Buy single article

Instant unlimited access to the full article PDF.

US$ 39.95

Price includes VAT for USA

Subscribe to journal

Immediate online access to all issues from 2019. Subscription will auto renew annually.

US$ 99

This is the net price. Taxes to be calculated in checkout.

Fig. 1
Fig. 2
Fig. 3


  1. Anderson CB, Griffith CR, Rosemond AD et al (2006) The effects of invasive North American beavers on riparian plant communities in Cape Horn, Chile: do exotic beavers engineer differently in sub-Antarctic ecosystems? Biol Conserv 128:467–474.

  2. Atalah A, Sielfeld WH, Venegas C (1980) Antecedentes sobre el nicho trófico de Canis g. griseus Gray 1836 en Tierra del Fuego. An Inst Patagon 11:259–271

  3. Briceño C, Knapp LA, Silva A et al (2013) Detecting an increase in an Endangered huemul Hippocamelus bisulcus population following removal of cattle and cessation of poaching in coastal Patagonia, Chile. Oryx 47:273–279.

  4. Burgiel SW, Muir AA (2010) Invasive species, climate change and ecosystem-based adaptation: Addressing multiple drivers of global change. Global Invasive Species Program (GISP), Washington DC, USA

  5. Cabrera A (1931) On some South American canine genera. J Mammal 12:54–67

  6. Collen P, Gibson RJ (2000) The general ecology of beavers (Castor spp.), as related to their influence on stream ecosystems and riparian habitats, and the subsequent effects on fish—a review. Rev Fish Biol Fish 10:439–461.

  7. Corti P, Wittmer HU, Festa-Bianchet M (2010) Dynamics of a small population of endangered huemul deer (Hippocamelus bisulcus) in Chilean Patagonia. J Mammal 91:690–697.

  8. Courchamp F, Chapuis J-L, Pascal M (2003) Mammal invaders on islands: impact, control and control impact. Biol Rev Camb Philos Soc 78:347–383

  9. Crego RD, Jiménez JE, Rozzi R (2016) A synergistic trio of invasive mammals? Facilitative interactions among beavers, muskrats, and mink at the southern end of the Americas. Biol Invasions.

  10. Dalziel IWD (1981) Back-arc extension in the southern Andes: a review and critical reappraisal. Philos Trans R Soc A 300:319–335

  11. Daszak P (2000) Emerging infectious diseases of wildlife—threats to biodiversity and human health. Science 287(80):443–449.

  12. Davis MA, Thomson K (2000) Eight ways to be a colonizer; two ways to be an invader: a proposed nomenclature scheme for invasion ecology. Bull Ecol Soc Am 81:226–230

  13. Dunn AM, Hatcher MJ (2015) Parasites and biological invasions: parallels, interactions, and control. Trends Parasitol 31:189–199.

  14. Glade A (1993) Red list of Chilean terrestrial vertebrates. Proceedings of the symposium “Conservation status of Chilean terrestrial vertebrate fauna,” Second. Corporación Nacional Forestal, Santiago, Chile

  15. Goburnova V, Bozzella MJ, Seluanov A (2008) Rodents for comparative aging studies: From mice to beavers. Age 30:111–119

  16. Gomez J, Gozzi A, Macdonald D (2010) Interactions of exotic and native carnivores in an ecotone, the coast of the Beagle Channel, Argentina. Polar Biol 33(10):1–12

  17. Hartman G (1994) Long-term population development of a reintroduced beaver (Castor fiber) population in Sweden. Conserv Biol 8:713–717

  18. Harvell CD, Mitchell CE, Ward JR et al (2002) Climate warming and disease risks for terrestrial and marine biota. Science 296:2158–2162.

  19. Humphrey PS, Péfaur E (1979) Glaciation and species richness of birds on austral South American islands. Occas Pap Museum Nat Hist Univ Kansas 80:1–9

  20. Jaksić FM, Yáñez JL (1983) Rabbit and fox introductions in Tierra del Fuego: history and assessment of the attempts at biological control of the rabbit infestation. Biol Conserv 26:367–374

  21. Jaksić FM, Yáñez JL, Rau JR (1983) Trophic relations of the southernmost populations of Dusicyon in Chile. J Mammal 64:693–697

  22. Jaksic FM, Iriarrte WA, Jiménez JE (2002) Invaders without frontiers: cross-border invasions of exotic mammals. Biol Invasions 4:157–173

  23. Jones CG, Lawton JH, Shachak M (1997) Positive and negative effects of organisms as physical ecosystem engineers. Ecology 78:1946–1957.[1946:PANEOO]2.0.CO;2

  24. Kolar CS, Lodge DM (2001) Progress in invasion biology: predicting invaders. Trends Ecol Evol 16:199–204.

  25. Letnic M, Ritchie EG, Dickman CR (2012) Top predators as biodiversity regulators: the dingo Canis lupus dingo as a case study. Biol Rev 87:390–413

  26. Lizarralde MS (1993) Current status of the introduced beaver (Castor canadensis) population in Tierra del Fuego, Argentina. Ambio 22:351–358

  27. Lizarralde M, Escobar JM, Deferrari G (2004) Invader species in Argentina: a review about the beaver (Castor canadensis) population situation on Tierra del Fuego ecosystem. Interciencia 29:352–356

  28. Mack RN, Simberloff D, Londsdale WM et al (2000) Biotic invasions: causes, epidemiology, global consequences, and control. Ecol Appl 10:689–710.[0689:BICEGC]2.0.CO;2

  29. MacNulty DR, Mech LD, Smith DW (2007) A proposed ethogram of large carnivore predatory behavior, exemplified by the wolf. J Mammal 88:595–605

  30. Markham BJ (1971) Presencia del “culpeo” (Dusicyon culpaeus) en la Isla Hoste, Tierra del Fuego. An Inst Patagon 2:162–165

  31. Novaro AJ, Funes MC, Walker SR (2000) Ecological extinction of native prey of a carnivore assemblage in Argentine Patagonia. Biol Conserv 92:25–33

  32. Novaro AJ, Moraga CA, Briceño C et al (2009) First records of culpeo (Lycalopex culpaeus) attacks and cooperative defense by guanacos (Lama guanicoe). Mammalia 73:148–150

  33. Osgood WH (1943) The mammals of Chile. F Mus Nat Hist 30:1–268

  34. Patenaude F (1984) The ontogeny of behavior of free-living beavers (Castor canadensis). Z Tierpshychol 66:33–44

  35. Pietrek AG, Fasola L (2014) Origin and history of the beaver introduction in South America. Mastozool Neotrop 21:355–359

  36. Pietrek AG, González-Roglich M (2015) Post-establishment changes in habitat selection by an invasive species: beavers in the Patagonian steppe. Biol Invasions.

  37. Randa L, Cooper D, Meserve P, Yunger J (2009) Prey switching of sympatric canids in response to variable prey abundance. J Mammal 90:594–603

  38. Schiavini A, Narbaiza C. (2015) Estado de situación de los conflictos derivados de las poblaciones caninas en Tierra del Fuego. Informe, Comité de Emergencia Agroganadero y de Alerta Sanitaria de Tierra del Fuego. Tierra del Fuego, Argentina. Pp. 37

  39. Shelton PC, Peterson RO (1983) Beaver, wolf and moose interactions in Isle Royale National Park, USA. Acta Zool Fenn 174:265–266

  40. Skewes O, Gonzalez F, Olave R et al (2006) Abundance and distribution of American beaver, Castor canadensis (Kuhl 1820), in Tierra del Fuego and Navarino islands, Chile. Eur J Wildl Res 52:292–296.

  41. Smith KF, Sax DF, Lafferty KD (2006) Evidence for the role of infectious disease in species extinction and endangerment. Conserv Biol 20:1349–1357.

  42. Smith KF, Acevedo-Whitehouse K, Pedersen AB (2009) The role of infectious diseases in biological conservation. Anim Conserv 12:1–12

  43. Tuhkanen S, Kuokka I, Hyvönen S et al (1999) Tierra del Fuego as a target for biogeographical research in the past and present. An Inst Patagon 19:4–107

  44. Valenzuela AEJ, Anderson CB, Fasola L, Cabello JL (2014) Linking invasive exotic vertebrates and their ecosystem impacts in Tierra del Fuego to test theory and determine action. Acta Oecol 54:110–118.

  45. Wallem PK, Jones CG, Marquet PA, Jaksic FM (2007) Identificación de los mecanismos subyacentes a la invasión de Castor canadensis (Rodentia) en el archipiélago de Tierra del Fuego, Chile. Rev Chil Hist Nat 80:309–325

  46. Wang X, Tedford RH, Van Valkenburgh B, Wayne RK (2004) Phylogeny, classification, and evolutionary ecology of the Canidae. In: Sillero-Zubiri C, Hoffmann M, Macdonald DW (eds) Canids: foxes, wolves, jackals and dogs. Status survey and conservation action plan. IUCN, Gland, Switzerland and Cambridge, UK, pp 8–20

  47. Wayne RK, Van Valkenburgh B, Kat PW et al (1989) Genetic and morphological divergence among sympatric canids. J Hered 80:447–454

Download references


We are indebted to Pablo Javier di Leo and Mónica Cecilia Mallino di Leo, who filmed the footage and generously delivered it to a park ranger. Also, we would like to thank Julio Escobar for sharing his vast field experience on introduced beavers. We are grateful to Bárbara Saavedra, Alejandro Vila, Alejandro Kush, and Custodio Millán for their help all along. We acknowledge faithful illustrations from Rodrigo Verdugo. Finally, we appreciate the support from the Wildlife Conservation Society Chile and logistic assistance from Karukinka Park.

Author information

Correspondence to Cristóbal Briceño.

Electronic supplementary material

(MP4 469 mb)

Appendix 1

(MP4 469 mb)



An adult Fuegian fox trots with a full adult muskrat in its muzzle, probably recently caught. Taken on a camera trap on the 28th of May of 2017 in Tierra del Fuego Island (54° 12′ 12″S, 68° 77′ 18″W)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Tadich, T.A., Novaro, A.J., Kunzle, P. et al. Agonistic behavior between introduced beaver (Castor canadensis) and endemic culpeo fox (Pseudalopex culpaeus lycoides) in Tierra del Fuego Island and implications. acta ethol 21, 29–34 (2018).

Download citation


  • Conservation implications
  • Culpeo attack
  • Endangered fox
  • Invasive species
  • Patagonia
  • Predatory behavior