American mink (Mustela vison) along the Beagle Channel, Tierra del Fuego: Ecology of an Introduced Predator

VALENZUELA, A.; RAYA REY, A.; SCHIAVINI, A.

San José

Congreso; Ecological Society of America (ESA) and Society for Ecological Restoration International (SER) Joint Meeting; 2007

Ecological Society of America

The American mink was released in the main  Tierra del Fuego island in the 1940’s, spreading into adjacent islands of the fuegian archipelago. Knowledge of the ecology of this introduced predator is essential for planning control and eradication strategies. We evaluated abundance, distribution, habitat characteristics and diet of mink in the Argentine coast of the Beagle Channel. We also constructed a habitat suitability model based on den positions and habitat map covers in a GIS. We estimated density of dens based in mink signs in relation to different habitat type (forest, shrubland, peat, grassland and muddy beach) and human presence along 600 m transects set every 5 km, and collected scats for diet analysis. We found mink dens only in forest and in shrubland. Their distribution was heterogeneous and unrelated to human presence. Most minks dens were established within 5-11 m from the coastline and in slopes between 5º-30º. The diet differed between winter and summer, with mammals being the most consumed item in both seasons, while in summer the consumption of fish, birds and crustaceans increased. Finally, we developed a predictive habitat distribution model for the mink along the coast of the Beagle Channel. These results allow to propose conservation strategies based on the establishment of high priority areas and corridors, recommending focus management on captures along coastal forests.