The use of molecular analysis in control (or eradicate) invasive North American beaver (Castor canadensis) in the Archipelago of Tierra del Fuego

FASANELLA MARIANA; POLJAK SEBASTIAN; LIZARRALDE MARTA

Mendoza, Argentina,

Congreso; X Congreso Internacional de Mastozoolog¨ªa; 2009

IFM- SAREM- CONICET

The use of molecular analysis in control (or eradicate) invasive North American beaver (Castor canadensis) in the Archipelago of Tierra del Fuego Fasanella M., Poljak S. & Lizarralde M. Centro Regional de Estudios Gen¨®micos, Universidad Nacional de La Plata, Av. Calchaqu¨ª km 23.5 4th floor, (1888) Florencio Varela, Buenos Aires, Argentina   Biological invasions have been identified as the second main cause of biodiversity loss and the main cause of species extinctions in island ecosystems. Particularly, the introduction of twenty-five breeding pairs of North American beaver (Castor canadensis) in the Isla Grande of Tierra del Fuego (Argentina) in 1946 has become a serious problem. Despite control efforts, the population has increased considerably; today, there are approximately 100,000 individuals with initial foci of colonization in the Brunswick Peninsula (Chile). Although the ecological and economic effects of invasive species have sometimes been evaluated, there has not been much attention devoted to the genetic structure of invading mammals. We have conducted molecular analysis of beavers from 3 subpopulations of the Archipelago of Tierra del Fuego, as a means of characterizing the genetic structure (at a macro and micro geographic scale) of the invasive population. We identified 7 D-loop haplotypes among 111 beavers. All of them were founded in the National Park subpopulation with a greatest haplotype diversity (¦Ä = 0.83) and a positive and significant autocorrelation out to 800 m (r = 0.193, p = 0.003) wich could probably explained by the control plan used in this area. Our results of AMOVA (Fst = 0.104, p < 0.001) suggest geographical barriers to gene flow and strong sociality and territoriality in beaver population. We suggested that an understanding of spatial genetic pattern and gene flow among subpopulations, are likely to have important implications for the proper design of an effective control strategy. Developing control strategies based on molecular data turns out to be not only efficient in the long term, but also creative, due to spatial genetic structure characteristics.