Shearwater Manx vs Audubon (1 Viewer)

Hi, I came across these pictures of a Shearwater photographed near Dominica in 2002 (http://www.geocities.com/secaribbirds/domanxshearwater.html). As there has been some discussion of the images, I thought I would kindly ask for some opinions here.

thanks
Niels

Manx

Hi Niels

As no-one else has posted on this tricky one, I'll have a bash and give a few comments. The pics are mine of Manx in Wales.

CONFESSION: I have never seen Audubon's, but I am familiar with Manx and have seen a few Little Shearwaters. Neither have I seen Levantine/Yelkouan Shearwater.

That said, the pics of the Dominica bird look OK for Manx to me and here's why:

The underwing pattern is good for a Manx. Check out particularly the dark area at the fore of the underwing that becomes a dark stripe reaching diagonally to the trailing edge and the small dark flank smudge tucked just under the forewing). Individual Manx's vary in the extent of dark feathering on the underwing, but the basic pattern is consistent.

The proportions of the wings and body look fine for Manx to me.

The dark neck smudge is also correct. And the bird has a pale area in front of the dark smudge that passes up behind the head on to the upper neck (not obvious on the second pic of the Dominica bird, perhaps because of the light direction?).

Pic 1 of the Dominica bird is a classic Manx shape from behind, with straight forewings and wings held in a V.

The bill looks long and thin, again good for Manx – wouldn't Audubon's have a shorter and thicker bill like a Little's?

And would Audubon's look that long winged?

However, the tail does look long for a Manx, but could that be the feet protruding?

Without experience of Audubon's I cannot say that the Dominica bird is definitely not one, but I can tell you that it looks like a Manx to me.

John

PS please not that due to very sunny conditions, at least two of my pics show burnt-out patches of white on the underside.

Thanks a lot John. You mention the possibility of protruding feet (the feet are visible on your own shots): the Dominica shots are not clear enough to destinguish tail from feet, I think.

thanks
Niels

It's not a Manx Shearwater, I can tell you that. I've not seen Audubon's so can't comment on that.
The leading edge to the underwing is way too broad and the demarcation of white to black on the face/head is way off for manxie as is the shoulder patch.

Niels: I agree, the Dominica shots are not clear enough to distinguish tail from feet. I meant that an indistinct combination of tail feathers and protruding feet might have given the impression of a too-long tail. It's only speculation on my part.

CJW: I can't see that the leading edge is "way too broad" compared with my third pic of a Welsh bird. The dark area on the leading edge below the carpel looks to my eyes exactly the same size and shape on my Welsh bird as on the Dominica bird (although the latter's dark patch looks more solid, which could be because of the lighting – e.g. the underwing of my bird is sunlit and the Dominca bird's underwing is shaded by its wing). The shoulder patch also looks fine to me. Your bird is indeed paler on the underwing than the Dominica bird, but Manx varies in the extent of dark in its underwing. And what's "way off" about the demarcation between white and black?

John

I think the underwing on Manxies is quite variable - however I have never seen one so messy on the neck sides. The bird reminds me strangely of a small dark....Yelkouan Shearwater.

Here are three Audobon's which I have never seen... the underwing also appears to variagle, but the third bird is a dead ringer for the mystery bird, structurally and plumage-wise.

http://www.amazilia.net/images/Birds/Shearwaters/AudubonsShear1.jpg
http://www.ontfin.com/Features/Pelagic/Audubons_Shearwater.jpg
http://www.mbr-pwrc.usgs.gov/id/htmsl/h0920pi.jpg

Audubon's has dark undertail covs

this doesn't

see Seabirds of the World (Harrison) page 69

and the neck smudge indicates Manx to me

Tim

Tim Allwood said:

Audubon's has dark undertail covs

Tim

Click to expand...

Hi Tim,
If you go again to the page with the Dominica sighting, there is a link to a discussion. One of the participants claim in there that up to 1/3 of the Audubon's have light undertail coverts. I cannot wouch for the truth of the number, but wanted to point out the disagreement. One of the pictures that Jane linked to shows the light undertail as well.

Thanks
Niels

Jane Turner said:

I think the underwing on Manxies is quite variable - however I have never seen one so messy on the neck sides. The bird reminds me strangely of a small dark....Yelkouan Shearwater.

Here are three Audobon's which I have never seen... the underwing also appears to variagle, but the third bird is a dead ringer for the mystery bird, structurally and plumage-wise.

http://www.amazilia.net/images/Birds/Shearwaters/AudubonsShear1.jpg
http://www.ontfin.com/Features/Pelagic/Audubons_Shearwater.jpg
http://www.mbr-pwrc.usgs.gov/id/htmsl/h0920pi.jpg

Click to expand...

Jane,
I have to disagree with you on saying that the third bird is spot on; that might be true for the underwing, but the tracing on the dark/light between eye and wing is different. On the Dominica bird, there is a light triangle up behind the ear coverts, and a dark triangle down after that; the tracing seems rather flat on all three of your pictures for Audubon.

I must admit that I am still undecided as to what this bird actually is.

thanks
Niels

My rather unscientific approach is that it doesn't feel like a Manxie... and belive me I have seen 100s of 1000s. Its not a Little, so I assume its Audubon's...

Jane

Can you pin down your doubts to actual features? At first I thought pic 1 looked fine for Manx but pic 2 looked far less like one. I came up with of a couple of reasons why this might be:

1. In pic 2 the light is shining from behind the bird, casting a shadow over the flank and neck. Even the chin looks darker than on the first image.

2. The bird is engaged in full-on flapping flight in pic 2 with bent wings, rather than the stiff-winged flight that is more typical of Manx here in UK. I've taken many a double-take over Manx in Madeira when they are flapping around. And because its flapping, it's very hard to tell the true angle of the head – we could be looking more at the top of its head and back of the neck in pic 2 than we are in pic 1.

What do you reckon?

John

It was pic 2 that put me off too

It something about the shape of the body ... its so yelkouan-like (lanky) ... and its funny what you say about the head.... turning the head a lot in flight is a yelkouan feature.... I am of course making a rash assumption that Audobon's has any similarity.

Anothr thing.. in pic one... there is a greyish cast to the uppers.. esp primaries... almost Like Little Shear secondaries. Manxies fade to brown!

Its all pretty subjective I'm afraid

Here are some yelkouans for illustration... shorter winged than the mystery.. but that same skinny body shape compared to a tubby manx

http://www.terra.es/personal5/arbmor/irbsf105.jpg
http://www.terra.es/personal5/arbmor/irbsf108.jpg

Now been looking up Audubon's Shear... and though the uts can be pale, am unimpressed by the structural features it is supposed to have

Compared with Manx and Yelkouan Shearwaters, appears shorter winged but longer tailed;

Are there any other B&W shears that should be considered... I mean pacific seabirds have turned up in the atlantic before... long shot I know! Its just not angled quite right to see if its got the pale rump sides of eg a Townsend's/Newell's... I guess pic one just about rules it out.. but pic two look a little more promising...

Off to vacation, so I will not be able to follow this for a week. I am looking forward to getting back to it when I come back!

thanks
Niels