Storm Petrel, pelagic near Sagres, Portugal - 06 Oct 2021 (1 Viewer)

[Shumi]

Hi All, pls kindly share your thoughts on this storm petrel that we saw on a pelagic near Sagres in early October. We were supposed to have seen "only" the European and Wilson's storm petrels on that trip. But among the tonnes of pictures that I took on that day I have now found this bird - and I note that it has clear white flashes on the upperwings (which should exclude the European) and at the same is too short-legged for a Wilson's.

I was wondering whether this could be a Band-rumped storm petrel (although the white band appears to be too broad for band-rumped)?..

I would very much welcome your thoughts. Thanks!

 

[Butty]

[bump]
Come along, someone...

 

[Bismarck Honeyeater]

Hi All, pls kindly share your thoughts on this storm petrel that we saw on a pelagic near Sagres in early October. We were supposed to have seen "only" the European and Wilson's storm petrels on that trip. But among the tonnes of pictures that I took on that day I have now found this bird - and I note that it has clear white flashes on the upperwings (which should exclude the European) and at the same is too short-legged for a Wilson's.

I was wondering whether this could be a Band-rumped storm petrel (although the white band appears to be too broad for band-rumped)?..

I would very much welcome your thoughts. Thanks!

I think I can see a flash of white on the underwing in the last photo, so Euro Petrel. It’s in quite a state of moult, so looked a bit different to others maybe.

 

[Butty]

I think I can see a flash of white on the underwing in the last photo

Looks more like light coming through the primaries. No white bar visible on inner underwing.

so Euro Petrel

Not enough white on flank. Moulting heavily-worn flight-feathers, so not juvenile, and much too much white on upperwing even for juvenile European storm-petrel. Apparently.

 

[Steve Lister]

Not sure about times of year but you could see Madeiran (or whatever it should be called now) Petrel off Sagres as they breed on the Berlengas islands further north. I and two Oxford Uni students mad on seabirds saw one from a fishing boat well offshore in August 1984.
Leach's is possible too of course.
I'm not saying this is either of them, just pointing out what is possible.

 

[Shumi]

I have addressed this question to Mar Ilimitado, the pelagic tour operator. I will post their reply here as soon as i get it.

I have viewed the last picture in max brightness and it does appear that there is no white patch on the underwing, as Butty pointed out above. It also occurs to me that the tail is slightly indented/bulged in in the middle (did not notice that originally), but not forked - and that would be another indication of Band-rumped (also called Madeiran) storm petrel/H. castro.

 

[Butty]

the tail is slightly indented/bulged in in the middle (did not notice that originally), but not forked

As the flight-feathers are in moult, there is also the possibility that the tail is too - so its shape should be treated with caution.

 

[njlarsen]

For what it’s worth: I have a book on tubenoses of the US by Howell. Of the species included there (which might be lacking something that could be seen in Portugal) the Grants/Madeiran were the best matches to these photos.
Niels

 

[Shumi]

So, I have received the reply from Mar Ilimitado - and turns out this was a Wilson's Storm Petrel after all... I quote the reply below. Out of all people I consulted with nobody suggested a Wilson's - yet another indication of just how treacherous those pelagic birds can be

"Regarding your question, the storm petrel in your photos is indeed a Wilson's Storm Petrel.
Below are a couple reasons why.

• Some individuals don't project the feet over the tail tipp, actually a key ID-feature, but there are some birds which don't (fly with the leggs tucked in, at least on occasion, don't know why exactly);
• The bird in your pictures shows heavy moult of remiges (is growing fresh inner primaries, blackish) and lacks part of the silvery greater upperwing coverts, therefore the pale band over the upperwing is incomplete;
• All this making it a bit odd looking, but the size and extension of the white patch on the rump and around the thighes, absolutely matches Wilson's, so does bill size, shape of the tail etc."