Small seabird with attractive grayscale pattern. Mostly black head set off by white collar, pencil-thin white streaks which form an eyebrow, and gray back. Sides show a scaly pattern. Short bill has a pale yellow tip. All plumages are fairly similar; breeding birds show bolder eyebrow streaks and darker throat. Breeds on offshore islands; found in small flocks on coastal waters. Dives underwater for fish.