A mainly gray or grayish brown petrel with a relatively heavy and pronounced forebody and more slender rear. Very pale faced with a relatively small, weak bill and indistinct brownish ‘M’ across back and wings. Highly pelagic, except near colonies. Great-winged Petrel is similar but uniformly brown, not gray, with a darker face. Providence Petrel is very similar but is, on average, less bulky in the forebody, appearing more slender, with a darker face. Providence also has much more contrasting white patches in the outer underwing, which in Murphy’s appear light gray at their palest. Trindade Petrel is somewhat similar, though appears more slender, and is more uniformly brown than the gray hue of Murphy’s Petrel. Silent at sea.