Estado actual de la distribución del castor Castor canadensis Kuhl 1820 (Rodentia) en el área continental de la región de Magallanes, Chile

In 1946, the beaver (Castor canadensis Kuhl 1820) was introduced in the tip of South America, which has generated great ecological and economic impacts in the austral ecosystem and forests. Since the beavers were release, they have been in a constant expansion through Tierra del Fuego, austral archipelago and in the continental areas of the Magellan region. In 1999 the Servicio Agricola y Ganadero (SAG) has developed a line of work about invasive species that affect in the field of agricultural production in Magallanes. The purpose of this work was updating the information about the distirbution of the beaver populations in the continent and controlling the potential outbreaks. SAG has hired a service of the beaver prospection in more than 3000 km of riversides and application of surveys in livestocks farm. During prospection, a new sign of the beaver is detected, but in areas where the species was have been recorded previously. These results show that despite the migratory pulses from Tierra del Fuego, the population has not been established in the continental area detonating to agriculture proposed. Nevertheless the potential of detection in conditions of low density added to the modification in the construction of dams and burrows could help to interpret these results. The temporality of the watercourses and the presence