Skua

Is this an Arctic Skua please? Taken Seahouses harbour, September
  • Hi-

    the colour and frequency of the feather edgings on the mantle and the proportions of the bill make this a Long Tailed for me

    -  did you take any more photos?

    Others may differ

    S

  • Thanks - took four pics, all very much the same. Just a slightly changed head angle. It just sat there and suddenly flew off.

  • Jim I think Seymouraves has a very valid point. I actually thought that the markings on the feather edgings on the mantle were confusing by artefacts due to oversharpening. You have the original photo so you can check the feather edgings - I am uploading below a couple of arctic scua photos I took some time ago for you to compare:

    Seahouses is rather out of the normal range of the long tailed scua but following Seymouraves's comment I checked for sightings and there have been sightings of long tailed scuas reported in the Farne Islands in 2007 and in 2014. So yours could well be a long tailed one - given the markings. 

  • Jim's skua is a juvenile though - both Arctic and Long-tailed juvs have barred plumage rather than the smooth unmarked plumage of adults. I have very little experience with juv skuas so can't say anything much else but I'll see if I can get another opinion.

  • I'm with Seymour on this one and would tend towards Long-tailed Skua for the reasons he gives (although photos from other angles would have been useful).

    Small numbers of Long-tailed Skuas pass down the east coast (and every other coast of Britain and Ireland!) every autumn, so one at Seahouses in September would not be something that I would consider out of range.

  • Aiki I was mainly focusing on head and bill, as indicated I thought the markings wouldn't help particularly as the photo is oversharpened and that creates artefacts which can be very confusing. This is not going to be easy though as I see that there is a certain amount of disagreement amongst experts too. Have a look at these links: BBA and British Birds, particularly the first one comparing directly the two species in question (I uploaded the second just for the description of the juvenile arctic).

    Jim, any chance to see the original photo - without the sharpening?

  • Thanks everybody - very grateful for your help. I think I somehow managed to sharpen the posted image twice, hence it looks rather "crunchy". Here is another shot which hopefully looks more realistic.

  • Ι've got a headache reading about the differences - thanks for the opportunity Jim. The feather markings from this angle couldn't help me at least to come to any conclusion based on what I read. I've picked up two points:

    1. The black on the tip of the bill is largely confined to the tip of the lower mandible on Arctic whereas there is more black on the bill of Long-tailed (about 40-50% of the bill, compared with 25-30% for the other species). Generally, the dark at the tip of the bill in juvenile Long-tailed extends back past the angle of the gonys, and frequently tapers about halfway towards the base of the bill along its cutting edges (p. 450).

    2. The buff eye liner - which in the photos of the second article appear to be a characteristic of the Long tailed, arctic being darker in this area.

    Both these would indicate this is a long tailed. Having said that I am waiting to see what Aiki will find out.

  • All of the visible features are entirely consistent with a juvenile Long-tailed Skua (cold plumage tones with no warm buff or 'rusty' tones, including on the nape and mantle fringes; a relatively short stubby bill, with the nail entirely dark and about half the length of the bill; the position of the gonys on the lower mandible - roughly in line with the rear end of the nail; the amount of pale mantle fringing).

    At least some of these features probably aren't outside of the normal variation of Arctic Skua, and some features (including bill proportions) may no be judged correctly from the posted photos - hence the questions about whether or not other photos were available. On balance though, it is very likely that it is a Long-tailed Skua.