The state's most important rivers are the Missouri, rising in southwest Montana and flowing north and then east across the state, and the Yellowstone, which crosses southeastern Montana to join the Missouri in North Dakota near the Montana border.
Distribution in South Africa. Hoverflies can be found all over the country between the sea-shores and the mountains. In total, there are at least 180 species recorded from South Africa. The number of species declines from the northeast to the southwest. However, some species have only or predominately been found in the Western Cape.
A variety of birds nest in the mosaic of habitats provided by the tundra. Red Phalarope, Northern Phalarope, Pectoral Sandpiper, Semipalmated Sandpiper, Buff-breasted Sandpiper, Dunlin, Lapland Longspur, and Savannah Sparrow are small species that nest in the area. few species are present year-round. Rock and Willow Ptarmigan are the most abundant birds during winter and are found in patches of willows where they feed mainly on the buds. Ravens are the most conspicuous winter birds. A few Gyrfalcons and Snowy Owls may also be present, depending on the abundance of prey.