Jouanin's Petrel vs Tropical Shearwater

In short

Jouanin's Petrel is a sooty-brown petrel with a long wedge-shaped tail, while the Tropical Shearwater is smaller and typically shows a more contrasting plumage with white underparts. Both species are found in overlapping oceanic regions, but their size and tail shape are key differentiators.

Identification tips

1. Look for the size difference: Jouanin's Petrel is noticeably larger. 2. Observe tail shape: Jouanin's has a longer, wedge-shaped tail. 3. Note plumage contrast: Tropical Shearwater typically shows more contrast with white underparts. 4. Consider the context: Both can be found in mixed feeding flocks, but size and tail shape are reliable differentiators.

Size

Jouanin's Petrel is larger and has a longer, more wedge-shaped tail compared to the smaller Tropical Shearwater.

Plumage

Jouanin's Petrel is uniformly sooty-brown to blackish-brown, whereas Tropical Shearwater usually has a more contrasting appearance with darker upperparts and white underparts.

Behaviour

Both species feed on fish, squid, and crustaceans, often engaging in pursuit-diving and surface-seizing. They may be seen in mixed-species feeding frenzies.

Habitat

Both species inhabit tropical and subtropical oceanic waters, often in similar regions, making habitat less useful for differentiation.