The rare Florida salt marsh vole (Microtus pennsylvanicus dukecampbelli) was discovered in spring 2004 by U.S. Fish and Wildlife Service (USFWS) personnel on the Lower Suwannee National Wildlife Refuge. The discovery of three individuals in the southern portion of the refuge renewed hope for effective recovery and protection of this rare animal. Further protection of the Florida salt marsh vole will rely on distribution surveys of the animal and conservation of potential habitat. This report details an effort by the U.S. Geological Survey to map potential habitat sites within the refuge. The Florida salt marsh vole is known to utilize a specific type of salt marsh called saltgrass (Distichlis spicata) as habitat. Hyperspectral imagery acquired in 2002 for mapping general intertidal habitats of the lower Suwannee River and estuary was re-evaluated for this specific habitat. The results of the mapping effort and field reconnaissance identified potential habitat in the salt marshes north and south of the Suwannee River. Saltgrass habitat was fieldidentified at flooded and elevated sites, near the shoreline and toward the marsh interior, and was found occurring with several other marsh species, including three-square sedge, smooth cordgrass, black needlerush, and glasswort. Image-derived saltgrass mapping was only 62% accurate. Positive identification of saltgrass from the imagery was hindered by the variety of environmental conditions and the co-occurrence of saltgrass with other species. Image-derived sites were mapped separately from field-verified locations. The tidal marsh around the Suwannee River delta itself did not support extensive saltgrass-dominant habitat. This was due largely to freshwater flow and dominance of freshwater marsh species in those areas. Where saltgrass was identified as a sparse understory, it could become the dominant cover under different conditions such as drought or decreased river discharge.