Athabasca rainbow trout

The Athabasca rainbow trout is a population of rainbow trout (Oncorhynchus mykiss), a fish in the family Salmonidae, native to the cold headwaters of the Athabasca drainage in Alberta, Canada. It is one of the few native rainbow trout populations in an Arctic Ocean watershed, because the Athabasca River is a tributary of the Mackenzie River system, which flows north into the Arctic Ocean. Robert Behnke's 1992 trout handbook treated it as a form of the Columbia River redband trout, and L. M. Carl of the Ontario Ministry of Resources considered it in 1994 a separate but unnamed subspecies, yet it is not now regarded as distinct from other rainbow trout. In winter it uses the largest and deepest pools of a stream as overwintering spots, and it spawns in spring, later than other rainbow trout, in streams with fine gravel free of silt and clay and with moderate flow. It was designated Endangered under Canada's Species At Risk Act in August 2019, and its main threats are invasive species, hybridization with introduced rainbow trout, fishing pressure, habitat loss, climate change and pollution.