Patagonian Desert whom 3,000 ended up in Buenos Aires separated by sexes to avoid their procreation. The boundary treaty of 1881 between Chile and Argentina bought most of the desert under definitive Argentine sovereignty; previously Chile had claimed varying now Argentine areas under claims of inherited colonial titles. In the few decades before and after 1900 the less dry parts of the Patagonian steppe experienced a sheep farming boom, transforming the region into one of the world's greatest exporters of ovine products. The area is sparsely populated today and those that do live here survive mainly by the raising of livestock such
Patagonian grasslands The region holds very diverse fauna. Mammals include Patagonian mara ("Dolichotis patagonum"), southern viscacha ("Lagidium viscacia"), Wolffsohn's viscacha ("Lagidium wolffsohni"), Patagonian weasel ("Lyncodon patagonicus"), Humboldt's hog-nosed skunk ("Conepatus humboldtii"), cougar ("Puma concolor"), Falkland Islands wolf ("Dusicyon australis") and guanaco ("Lama guanicoe"). Threatened species include Patagonian mara ("Dolichotis patagonum"), guanaco, South American gray fox ("Lycalopex griseus") and South American fur seal ("Arctocephalus australis"). Bird include Darwin's rhea ("Rhea pennata"), Patagonian tinamou ("Tinamotis ingoufi"), black-chested buzzard-eagle ("Geranoaetus melanoleucus"), peregrine falcon ("Falco peregrinus"), band-winged nightjar ("Systellura longirostris"), Patagonian mockingbird ("Mimus patagonicus") and Patagonian yellow finch ("Sicalis lebruni"). Endemic birds found north of the