Arctic cisco
The Arctic cisco, also known as Arctic omul, is an anadromous species of freshwater whitefish that inhabits the Arctic parts of Siberia especially Yenisey Gulf. It can also be found in Alaska and Canada. It has a close freshwater relative in several lakes of Ireland, known as the pollan, alternatively regarded as conspecific with it, or as a distinct species.
Taxonomy
The freshwater omul of the Lake Baikal, formerly considered a subspecies Coregonus autumnalis migratorius of the Arctic cisco, has no close genetic relationship to it and is now classified as a separate species, Coregonus migratorius.Description
The Arctic cisco has a relatively small head with a non-prominent snout. It has a metallic silver body, a brown or dark green back, and nearly colorless fins. It has neither spots nor teeth on its jaw. It does not have a patch of teeth on its tongue. It can reach 50 cm in length and weight up to 2 kg but is usually less than 40 cm in length and 1 kg in weight.Distribution and habitat
The Arctic cisco can be found in the Beaufort Sea, Colville River delta, and freshwater drainages east of the Sagavanirktok River. It can be found in several drainages in the Northwest Territories and Siberia, such as the Chaun River, and is not often found east of Point Barrow.Food chain
Diet
The Arctic cisco preys upon plankton, crustaceans and small fishes.Predators
Predators of the Arctic cisco include marine mammals, seabirds and large fishes such as the Dolly Varden trout and burbot.Behaviors
Reproduction
The Arctic cisco is able to spawn at 8 or 9 years of age. Females may only be able to spawn two or three times in their life, and do not necessarily produce eggs every year.The Arctic cisco reproduces in September. It does not reproduce in Alaskan waters but does reproduce in the Mackenzie River.
Females have up to 90,000 eggs.