Non-Migrant: No. All populations of this species make significant seasonal migrations.
Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).
Locally Migrant: Yes. At least some populations of this species make annual migrations of over 200 km.
Migrates between northerly summer range and winter range to south. Inshore movement in summer dramatic and predictable, coincides with breakup of ice cover. Annual migrations appear responsive to ice formation and drift. (Leatherwood and Reeves 1983).