Lake Superior other Great Lakes fish, populations have also been affected by the accidental or intentional introduction of foreign species such as the sea lamprey and Eurasian ruffe. Accidental introductions have occurred in part by the removal of natural barriers to navigation between the Great Lakes. Overfishing has also been a factor in the decline of fish populations. Lake Superior Lake Superior (; ), the largest of the Great Lakes of North America, is also the world's largest freshwater lake by surface area, and the third largest freshwater lake by volume. The lake is shared by the Canadian province of Ontario to
Upper Klamath Lake Upper Klamath Lake Upper Klamath Lake (sometimes called Klamath Lake) (Klamath: ?ews, "lake" ) is a large, shallow freshwater lake east of the Cascade Range in south-central Oregon in the United States. The largest body of fresh water by surface area in Oregon, it is approximately long and wide and extends northwest from the city of Klamath Falls. It sits at an average elevation of . In the early 20th century, most of the wetlands and marshes surrounding the lake were drained for agricultural purposes, damaging the larger habitat. The lake's water has been used to support the federal Klamath