Amazon river dolphin widespread river dolphins. They are present in six countries in South America: Bolivia, Brazil, Colombia, Ecuador, Peru, and Venezuela, in an area covering about . The boundaries are set by waterfalls, such as the Xingu and Tapajós rivers in Brazil, as well as very shallow water. A series of rapids and waterfalls in the Madeira River have isolated one population, recognized as the subspecies "I. g. boliviensis", in the southern part of the Amazon basin in Bolivia. They are also distributed in the basin of the Orinoco River, except the Caroni River and the upper Caura River in Venezuela. The
Middle Fork American River Middle Fork American River The Middle Fork American River is one of the three main branches of the American River in Northern California. The river flows from its headwaters in the Sierra Nevada, in a generally southwest direction, to join the North Fork American River near Auburn. The main stem of the river begins along the Sierra Crest, on the south flank of Granite Chief near Squaw Valley Ski Resort west of Lake Tahoe. It flows west then southwest into French Meadows Reservoir, which is impounded by the L.L. Anderson Dam. Below the dam the Middle Fork enters a rugged