Arctic cisco

The Arctic cisco (Coregonus autumnalis), also known as Arctic omul (Russian: Омуль), 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.