Some Native American tribes, particularly those on extremely windy reservations, have been pursuing deals lately with wind-power developers, seeing the projects as potentially large and steady sources of income. Overall, Indian reservations are some of the poorest areas in the United States, but federal energy officials and others hope that a boom in wind power projects on Native land will become, like casinos, a big, reliable source of income for areas that sorely need the funds. So far, only one large wind project has been completed on tribal land — a 50-megawatt wind farm on Campo land near San Diego — but other farms are on the way. The Lower Brule Sioux tribe recently signed a deal with a Spanish utility for a 225-megawatt wind farm on their reservation land in South Dakota. And another nearby Sioux tribe, the Rosebud Sioux, has already erected one turbine to power its casino and is about to sign a deal with wind developer Distributed Generation Systems to build a 30-megawatt wind farm on 50 acres of their reservation land — an arrangement that’s expected to bring in about $5 million over 20 years.