Dark brown seabird with silvery flashes on underwings. Smaller than most gulls. Wingbeats are quick and snappy but deep. In the North Pacific, very similar to Short-tailed Shearwater but slightly larger with longer bill and more gradually sloping forehead. Brown plumage reminiscent of Flesh-footed Shearwater but narrower-winged. Where common, seen from shore more frequently than other shearwaters, often in massive flocks.