U.S. Fish and Wildlife Service - Midwest Region: Service employee Mary Henson and Hanna Mello (USGS - LaCrosse), at Hog Island Creek, filling trays with silty sediment to be used in a study to determine the amount of lampricide in sediment and water
U.S. Fish and Wildlife Service - Midwest Region: Fish Biologist Mary Henson takes a water sample during a study designed to determine lampricide concentrations in sediment and water at Hog Island Creek