Sheefish in Detail.

Sheefish (Stenodus leucichthys) is the largest member of the whitefish subfamily weighing up to 60 pounds and 42 inches in length north of the Arctic Circle. Most sheefish are harvested around 16-30 inches and 25lbs.
Sheefish can spawn annually however most will spawn every other year. Eggs are released without preparing beds and settle downstream in gravel and river bottom crevasses.

While young sheefish feed primarily on insects, as they get older they prefer to feed upon other fish.

Sheefish can migrate over 1,000 miles in a year. They are abundant in the Kuskokwim, Yukon, Selawik, Kobuk drainages. Small populations exist in the rivers of Norton Sound.