INVADER SPECIES IN ARGENTINA: A REVIEW ABOUT THE BEAVER (Castor canadensis) POPULATION SITUATION ON TIERRA

ild furbearers have aes-thetic, economical, and cultural value. On the southernmost tip of Patagonia, native furbearing species are not abundant (Liz-arralde and Escobar, 2000; Lizarralde and Elisetch, 2001). For that reason, in 1946, 25 pairs of beaver (Castor canadensis) were introduced on the Río Claro of Isla Grande (Tierra del Fuego Archipelago, Argentina) by the federal government (Figure 1). The absence of most natural predators and human hunting, and the availability of suitable feeding and lodg-ing conditions favored rapid populatio