General

Juan Fernandez Petrel: Medium to large gadfly petrel with white underparts and front, gray upperparts with white-gray scaling on back; black-gray around eye and crown. Black-gray on rump, tertials and cap, extending to most of the ear coverts and secondary coverts, forms an "M" pattern on the upperparts; rest of upperparts gray or brown-gray with scaly pattern. Legs and basal part of feet are pale pink. The rest of the feet including the outer toe are black. Bill is long and black. Iris is dark brown. The female and juvenile are similar to adult.

Breeding and Nesting

Juan Fernandez Petrel: Their breeding habitat is high elevation ridges, above 2,460 feet, where they dig a six to ten foot deep tunnel. The females lay a single white egg in mid-November, and both adults take turns incubating the egg for about 60 days. The chick hatches in mid-February and is fed by both parents for about 90 to 100 days before fledging in May.

Foraging and Feeding

Juan Fernandez Petrel: These petrels forage for squid, small fish and crustaceans by diving into the water and picking prey from the surface. They are often found in areas of upwelling, where cool, nutrient-rich water rises to the surface, resulting in an abundance of prey. They also depend on tuna and other large predatory fish to drive prey to the surface.

Vocalization

Juan Fernandez Petrel: Grunting and wailing noises made at nesting grounds. Makes an abrupt chattering squawk, "chrr-churrk-chrr" as an advertising call. It sounds similar to a recently fledged Common Blackbird's begging call.

Similar Species

Juan Fernandez Petrel: Bonin Petrel has more black on the underwing and Newell's Shearwater has more uniform, dark upperparts.