Хендерсонский тайфунник Pterodroma atrata

A typical uniformly grayish-brown petrel with pale mottling at the base of the bill that gives it a somewhat “frosted” facial appearance. Pale bar along the leading edge of the underwing between the body and elbow is evident in flight. Highly pelagic, visiting land only to nest. Similar to Kermadec Petrel, but lacks the white primary shafts in the upperwing of that species and is overall more uniformly colored. Providence Petrel is similar but appears much heavier-chested and paler-faced, with more extensively mottled gray-brown tones across the body. Herald Petrel is very similar, but has much more contrasting dark-and-light underwing pattern. Henderson Petrel is silent at sea.