Welcome to the University of Montana’s Flathead Lake Biological Station, which is located on the Flathead Indian Reservation and the shores of Flathead Lake, Montana. Flathead Lake is the 79th largest of the natural freshwater lakes in the world and is renowned for its water quality and clarity. The lake’s pristine water results from its watershed being mainly National Park, Wilderness and managed forest lands (more than 60%); having a relatively low human population; being dominated by very old, low nutrient geology; receiving high amounts of precipitation (mostly as mountain snow); and rapid flushing of the Lake (about 2.2 years for all the water to be replaced).