Small, dark seabird, but large for a storm-petrel. Blackish-brown plumage with paler brown upperwing bar. Flight style and long, pointed wings and long, forked tail help separate it from other dark-rumped storm-petrels. Deeper wingbeats than Ashy or Leach's Storm-Petrel with a rather smooth and lazy flight. Found singly or in flocks resting or feeding on the water.