SciELO - Scientific Electronic Library Online

 
vol.80 issue3Trophic ecology of the wild boar (Sus scrofa) in ChileFirst records of three species of Oxycraspedus Kuschel (Coleóptera: Belidae) in Argentina and use of a predictive model to compare their potential distribution with the range of their host-plant, Araucaria araucana author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand

Journal

Article

Indicators

Related links

Share


Revista chilena de historia natural

Print version ISSN 0716-078X

Abstract

WALLEM, PETRA K; JONES, CLIVE G; MARQUET, PABLO A  and  JAKSIC, FABIÁN M. Identifying the mechanisms underlying the invasion of Castor canadensis (Rodentia) into Tierra del Fuego archipelago, Chile. Rev. chil. hist. nat. [online]. 2007, vol.80, n.3, pp.309-325. ISSN 0716-078X.  http://dx.doi.org/10.4067/S0716-078X2007000300005.

Castor canadensis is considered an archetypical ecosystem engineer, which modifies the state of biotic and abiotic factors through non-trophic interactions. This species was introduced by the Argentinean government into Tierra del Fuego island in 1946, and subsequently colonized autonomously the neighboring islands of Navarino, Dawson and Hoste. Currently this invader occupies contrasting ecosystems such as the Magellan subpolar beech forest and Patagonian scrub and steppe. This ability to colonize contrasting habitats suggests that beaver expansion will be limited mainly by hydrological resources, threatening to colonize the complete extent of temperate beech forests on the mainland (from 35 to 55° S). The present review proposes three hypotheses regarding the underlying mechanisms to this successful invasion: natural enemy escape, resource opportunities, and self-facilitation through non-trophic interactions. Current knowledge regarding beaver colonization and foraging behavior (e.g., habitat selection independently of forest availability, irruptive population growth, and apparent selective exploitation of Nothofagus pumilio, dominant species in the Magellan forest) suggests that enemy escape and resource opportunity are the main mechanisms underlying this invasion. The observation of higher densities of active colonies, where the extent of beaver habitat modification is larger, suggests that self-facilitation may be relevant to the success of this invasion. Current information does not allow testing these hypotheses, but it provides a framework to develop future investigations regarding this invasion in Tierra del Fuego

Keywords : Castor canadensis; Patagonia; enemy escape; resource opportunity; non-trophic interactions.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )

 

Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License