Blue Petrel vs Salvin's Prion

In short

The Blue Petrel and Salvin's Prion can be distinguished primarily by their bill structure and plumage patterns. Blue Petrels have a distinct dark cap and a more robust bill, while Salvin's Prions show a more uniform head pattern and a slender bill. Both species are pelagic and can be challenging to differentiate at sea, but these features are key in close views.

Identification tips

1. Look for the dark cap and contrasting white face of the Blue Petrel. 2. Note the bill shape: Blue Petrels have a more robust bill compared to the slender bill of Salvin's Prion. 3. Check for the 'M' pattern on the upper wings of the Blue Petrel. 4. Use close views to assess head pattern differences, as Salvin's Prion has a more uniform head coloration.

Size

Both species are similar in size, but the Blue Petrel is slightly larger overall.

Plumage

Blue Petrels have a striking dark cap that contrasts with their white face and throat, while Salvin's Prions have a more evenly colored head with less contrast between the cap and face. The Blue Petrel also has a more pronounced 'M' pattern on its upper wings.

Behaviour

Both species exhibit similar flight patterns typical of petrels, with gliding and occasional flapping. Observing behavior alone may not be sufficient for identification.

Habitat

Both species are pelagic and are often found in similar oceanic habitats, making habitat a less reliable distinguishing factor.

Voice

Vocalizations are not typically used to distinguish these species in the field, as both are generally silent at sea.