Yakama man, Twitmix and his horse, Washington. Photo: 1908. - The Confederated Tribes and Bands of the Yakama Nation, or simply Yakama Nation (formerly Yakima), has nearly 10,000 enrolled members, living in Washington state. Their reservation is along the Yakima River. Many tribal members engage in ceremonial, subsistence, and commercial fishing for salmon, steelhead, and sturgeon in the Columbia River and its tributaries within land ceded by the tribe to the United States.