White-faced Storm-Petrel vs Cook's Petrel

The White-faced Storm-Petrel is notable for its distinctive pogo-stick flight and white face with a dark cap, while Cook's Petrel is more streamlined with a grey head and lacks the bouncing flight. Both species are seabirds but differ in flight style and head coloration.

1. Flight style: Look for the distinctive pogo-stick flight of the White-faced Storm-Petrel. 2. Head coloration: Note the white face with a dark cap on the White-faced Storm-Petrel versus the grey head of Cook's Petrel. 3. Size and shape: Cook's Petrel is larger and more robust, while the White-faced Storm-Petrel is smaller and more delicate. 4. Location: Consider the oceanic region where the bird is observed, as their ranges differ.

Cook's Petrel is generally larger and more robust than the smaller, more delicate White-faced Storm-Petrel.

White-faced Storm-Petrel has a white face with a dark cap and eye patch, brown upperparts, and white underparts. Cook's Petrel has a grey head, darker upperparts, and a more uniform greyish-white underbody.

White-faced Storm-Petrel is known for its unique, bounding flight where it appears to bounce off the water surface. Cook's Petrel exhibits a more typical, gliding flight pattern.

Both species are pelagic and found offshore, but White-faced Storm-Petrel is more likely to be seen in the Atlantic and southern oceans, while Cook's Petrel is primarily found in the Pacific Ocean.