Monte Desert not only common, but tall cacti even appear in the more hospitable areas of the desert. The fauna of the area is also very similar to that of the Patagonian Desert, only in greater diversity and number due to the Monte's more hospitable conditions. Small mammals like mice abound and larger animals like the guanaco and burrowing owl can be found as well. Monte Desert The Monte Desert is a South American ecoregion, lying entirely within Argentina and covering approximately the submontane areas of Catamarca, La Rioja, San Juan, San Luis and Mendoza Provinces, plus the western half of La
Patagonian Desert contributing to the gravel sediments covering parts of the Patagonian. The desert is quite windy as well, a result of the rain shadow effect and descending cool mountain air. This wind helps make the Patagonian one of the largest sources of dust over the South Atlantic Ocean. On the west the Patagonian grasslands portion of the Patagonian Desert are bounded by nothofagus forests of the Magellanic subpolar forests. Volcanic rocks covers more than 120,000 km of the Patagonian Desert, mainly in the "Somun Cura Massif" (i.e. North Patagonian Massif) and the "Deseado Massif". Some other volcanic areas include the Pali-Aike