Shearwater ID: SOSH, SRTS, or ?

[simonthetanner]

I participated in a pelagic trip off the Oregon coast about a year ago; it was a whirlwind day, and I came home with hundreds of shots and almost 20 lifers. We had 5 species of shearwater on that trip: SOSH, BULS, PFSH, FFSH, and SRTS. I got decent photos of the first 4, but never found any clear shots of the SRTS. Recently I was going through my photo archive, and found a bird that looks like it might be a candidate for one of the 2 SRTS we had flying around that day. Unfortunately only the last shot was in focus, so IDing it requires working with the silhouette a bit. I'm not much of a pelagic guy, so I'm asking for help here.

It seems to me to be either SOSH or SRTS, as the legs and bill appear full black. The underwing pattern does seem to resemble FFSH a bit, but otherwise I don't se any other field marks supporting that ID. The reason I am wondering if it is SRTS is because of the steep angle between the bill and forehead, the crooked/swept wings, and generally dull underwing coloration. Bill size is inconclusive to my eye but seems fairly short, but someone more familiar with shearwater silhouettes might be able to pick it out.

I've attached a link to Google Drive with 4 shots. I have a couple other photos from the sequence, but I imagine these will be the most useful. The bird may not be IDable from my shots, but perhaps someone will be able to spot something I'm missing. Thanks much for your time and help.

Shearwater 1 Google Drive
Shearwater 2 Google Drive
Shearwater 3 Google Drive
Shearwater 4 Google Drive

 

[akandula]

That dark brown compact appearance with silver based primaries made me think Murphy's Petrel at first glance.

But that would be shockingly rare at this time of the year, so definitely wait for more opinions.

[AlexHenry]

This bird, especially in the 4th photo, appears to have an almost nonexistent neck. Also the underwing coverts look pretty solid brown without a trace of the silvery that Sooty Shearwaters have. This doesn't look like a Sooty Shearwater to me.

As @akandula mentions, the compact, short necked shape reminds me more of a petrel or fulmar than a shearwater. But I don't have much experience with Short-tailed Shearwaters and none with Murphy's Petrel, so I don't think I'm qualified to say any more.

[Tony Leukering]

Why not a dark Northern Fulmar? The bird doesn't strike me as any sort of Pterodroma, though I've seen only four species (Black-capped, Mottled, Cook's, and Murphy's). Fulmars usually hold their heads in flight with the bill angled downward, as in the photos, and the bull-necked appearance certainly fits fulmars.

[simonthetanner]

Thank you for the insights here, everyone. I'm thinking the fulmar option makes the most sense, as we had hundreds of them on that trip and the stocky, short neck is a really good point. That would also fit the coloration under the wing. Also supporting that ID is the stiff, flat wing posture visible in some of the shots. The only thing that doesn't quite seem right to me is the bill — I can't judge the color well from these shots, but it does seem awfully slender for a fulmar and almost somewhat "hooked" at the tip (especially evident in the 4th shot). But it's really hard to judge details like that from such low quality images, and the overall shape/posture do fit fulmar very well. 

I'd go with that ID, unless anyone else spots something else.

Thank you again to everyone for your help.

[blackburnian]

The bill seems a bit thin for Fulmar, but that may be due to elements of the photo. I like Fulmar as well.