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.
Males arrive in breeding areas in late May and early June, migrate south to winter range from early August to early October. Females and young migrate south beginning in October (e.g., see Ragen et al. 1995 for information on migration from St. Paul Island south through the Aleutian Islands), gone from Bering Sea by late November; begin returning north to rookeries in March (Reeves et al. 1992). San Miguel Island population probably stays in California waters all year.