Leaf River (French: Rivière aux Feuilles; Inuktitut: Kuugaaluk meaning "the large river" or Itinniq meaning "where there are spring tides") is a significant river located in the northern region of Quebec, Canada. Situated at the northern limit of the tree line within the Nunavik territory, the river flows from Lake Minto northeast across the Ungava Peninsula into Leaf Bay, which is an arm of Ungava Bay.
Geography and Hydrology The river originates at an elevation of approximately 181 meters (594 feet) in Lake Minto. Its total length, including the course through Lake Minto, is approximately 480 kilometers (300 miles). The river basin covers a vast area of about 42,500 square kilometers (16,400 sq mi). At its mouth, located at the head of Leaf Bay near the Inuit community of Tasiujaq (formerly known as Ivujivik's northern neighbor in some contexts, though Tasiujaq is a distinct community), the river enters Ungava Bay. The average discharge rate is estimated at 590 cubic meters per second (21,000 cu ft/s).
The river remains ice-free for approximately 60 days annually. It is noted for being navigable by canoe for its entire length without the need for portaging, as it lacks impassable waterfalls or severe rapids. Major tributaries include the Charpentier River, Nedlouc River, Descareaux River, Daunais River, Goudalie River, Vizien River, Brissard River, Qijuttuuk River, Cohade River, Tuktu River, Dufreboy Creek, Viennaux River, Papijjusaq River, Peladeau River, and Fanfan River.
Ecology The Leaf River region is ecologically significant as it supports the Leaf River caribou herd (LRCH), a migratory forest-tundra ecotype of the boreal woodland caribou (Rangifer tarandus caribou). This herd is distinct for its migration patterns, moving between the tundra and the southern boreal forest. The river valley serves as a critical corridor and calving area for these animals.
History and Etymology The English name "Leaf River" has been in use since at least the late 19th century. It is widely believed to have been derived from the sparse growth of Arctic willow and birch trees found along its banks, which provide leaves in a region otherwise dominated by tundra vegetation.
In 1898, the river was explored by Albert Peter Low. In 1912, it was visited by Robert J. Flaherty. The French name Rivière des Feuilles was assigned in the early 20th century and standardized to Rivière aux Feuilles in 1925. The Hudson's Bay Company established a trading post at the river's mouth around 1905, primarily for fishing salmon and harvesting porpoises. In 1976, Bob Davis undertook an expedition of the river.
The area is characterized by rugged glacial valleys, discontinuous permafrost, and a landscape that marks the transition between the arctic tundra to the north and the boreal forest to the south.