Black-bellied Storm Petrel vs White-faced Storm Petrel

Black-bellied Storm Petrel

Fregetta tropica

Small52 gMarine

They are usually black with a white band over the rump and white under the wings and on the flanks. A broad black stripe runs down the center of the belly, but may be broken or absent altogether. They have long legs, so the feet can be seen beyond the tail in flight. The legs and feet are black. They are silent mostly at sea. Noises can be heard from the breeding colonies; birds on the ground give a drawn-out shrill whistle.

ID text from Wikipedia, CC BY-SA 4.0

Photo: Ingvild Riska · CC BY 4.0

White-faced Storm Petrel

Pelagodroma marina

Small47 gMarine

Commonly, the white-faced storm petrel is 19 to 21 centimetres (7.5 to 8.3 in) in length with a 41 to 44 centimetres (16 to 17 in) wingspan and 40 to 70 grams body mass. The key characteristics of this species include dark bill, tarsi, toes and claws. It has a pale brown to grey back, rump and wings with black flight feathers. It is white below, unlike other north Atlantic petrels, and has a white face with a black eye mask like a phalarope. Its distinctive grey-brown dorsal side plumage makes it one of the easier petrels to identify at sea from a distance.

ID text from Wikipedia, CC BY-SA 4.0

Photo: iNaturalist user: paloma · CC0

Photos and recordings are credited to their authors under the licence shown. Full profiles: Black-bellied Storm Petrel and White-faced Storm Petrel.