The Patagonian steppe of Argentina is a vast and sparsely populated area where populations of native wildlife have been undermined by human activities. Guanaco (Lama guanicoe) is one of the two species of wild South American camelids and one of the few large, native herbivores of the region.

Over the last century, guanacos have experienced a dramatic decline in abundance and range distribution, mainly due to illegal hunting and livestock raising through competition for food and habitat modification. At present, only about 500000 guanacos are left and most of them inhabit Argentinean Patagonia. Though natural reserves may protect wild populations of native species, these encompass relatively small and isolated areas.

Therefore, conservation of free-ranging wildlife inhabiting this human-dominated landscape should be stated as a priority if long-term persistence of these populations wants to be achieved. Most lands are ruled by sheep farmers that have a negative opinion towards the guanaco because they diminish sheep food resources. Consequently, guanacos are killed or chased out of these large ranches to enhance field productivity. In the last few years, shearing of guanacos has arisen as a complementary activity for sheep farmers; furthermore, nowadays most wildlife agencies of Patagonian provinces are promoting this activity. However, the effect of shearing wild guanacos has not been adequately evaluated yet. Hence, we plan to evaluate the disruption of social structure, increase of mortality and decrease of reproduction due to shearing of wild guanacos. Fieldwork will be conducted in a 40000 ha sheep-ranch located in the province of Río Negro, Argentina; this ranch has been shearing free-ranging guanacos since 2003. Shearing of wild guanacos could play an important role in the conservation of this vulnerable species only if it imposes no detrimental effects on their behaviour and population dynamics.