Southern Patagonian Ice Field in the area, among which are the Upsala (765 km), Viedma (978 km) and Perito Moreno (258 km) in the Los Glaciares National Park in Argentina, and the Pío XI Glacier or Bruggen Glacier (1,265 km, the largest in area and longest in the southern hemisphere outside of Antarctica), O'Higgins (820 km), Grey (270 km) and Tyndall (331 km) in Chile. The glaciers going to the west flow into the fjords of the Patagonian channels of the Pacific Ocean; those going to the East flow into the Patagonian lakes Viedma and Argentino, and eventually, through the rivers "de la Leona"
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