Bear River Migratory Bird Refuge (MBR) lies in northern Utah, where the Bear River flows into the northeast arm of the Great Salt Lake. The Refuge protects the marshes found at the mouth of the Bear River; these marshes are the largest freshwater component of the Great Salt Lake ecosystem. Since these marshes are in turn surrounded by arid desert lands, it is little wonder that they have always been an oasis for waterfowl.