This release includes eight data files that provide concentrations of mercury (Hg) chemical species and ancillary chemical and physical data that quantify and document aspects of the Hg cycle in stream and rivers located on tribal lands of the Bad River Band of Lake Superior Chippewa. These files were transferred to the U.S. Geological Survey by Lacey Hill Kastern, Natural Resources Department, Bad River Band of Lake Superior Chippewa in May, 2018. Files listed as Child Items in this release include data on Hg concentrations in: bald eagle feathers (Mercury Concentrations in Bald Eagle Feathers, Bad River Watershed, Wisconsin, 2014 - 2016.csv), bed sediment (Mercury Concentrations in Bed Sediment, Bad River Watershed, 2006-2015.csv), fish tissue (Mercury Concentrations in Fish Tissue, Bad River Watershed, Wisconsin, 2004-2013.csv), green frog tissue (Mercury Concentrations in Green Frog Tissue, Bad River Watershed, Wisconsin, 2012-2013.csv), litterfall (Mercury Concentrations in Litterfall, Bad River Watershed, Wisconsin, 2012-2018.csv), river otter hair (Mercury Concentrations in River Otter Hair, Bad River Watershed, Wisconsin.csv), surface waters (Mercury Concentrations in Surface Waters, Bad River Watershed, Wisconsin, 2006-2016.csv), and wild rice (Mercury Concentrations in Wild Rice, Bad River Watershed, Wisconsin, 2006.csv). Attributes describing the contents of each of these data files are provided in the .xml file that accompanies each Child Item. Note that documentation of some data sets was incomplete as received from the Natural Resources Department. Any data items in the .csv files that were not available are marked with "NA" indicating not available. This data release includes as much documentation as was provided to the U.S. Geological Survey. Neither sample collection nor Hg analyses were performed by the U.S. Geological Survey, New York Water Science Center.