The Otter River is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. The National Map, accessed January 3, 2012 river in Houghton County, Michigan, in the United States. It was home to the last known population of Michigan Grayling. No grayling have been seen or caught in the river since 1938.
See also List of rivers of Michigan
References
Michigan Streamflow Data from the USGS