Fairly common on the ocean in winter; prefers to be farther offshore, but also seen in bays and harbors. When close to shore, often outnumbered by other scoter. Common in Great Lakes, where often close to shore and in channels. ID: White secondaries hard to miss in flight and usually visible on sitting birds with patient observation. Can usually be picked out by larger size from other scoter. Big, with a neck on steroids, particularly broad at base, and overall ‘mean’ demeanor. Neck tilted forward when outstretched. Long pointed face, concave from forehead to bill (straight in SUSC) though sometimes difficult to judge. Small bill with large feathered area between bill and eye, often appearing as pale area (different shape from SUSC). Pale loral and cheek patches variable, sometimes absent (young males?) to bold (young females). Young males start to show adult-type characters late in winter and are adult-like by second winter. Young birds have pale bellies but darker than other scoter. Adult males surprisingly small-billed on close inspection. White eye patch usually visible at long range. Oft-cited contrasting brown flanks difficult to see in the field.