Broad cisco (Coregonus nasus)
The range of this whitefish is mainly in the basin of the Arctic Ocean from the Kanin Peninsula to Chukotka and Alaska. This fish is also dwelling in the Anadyr and Penzhina River basins belonging to the Pacific Ocean. Broad cisco is interesting in that it prefers to feed in the lakes, but it can only reproduce in big rivers. This species lays eggs not on the sandy and pebble bottom (like other whitefish), but into the sludge (slush-ice), accumulated in the water column, in the holes below the riffles.
The most common broad cisco weight in catches is 1-2 kilograms. This species can reach large size (the length up to 75 cm, the weight over 10 kilograms); such fish are always found in the lakes that do not have permanent connection with the main river. During the record water levels, the broad cisco juveniles are isolated in such reservoirs. The fish cannot leave the lake to go out for spawning, and continue to feed and eat.