Can anyone assist me in identifying this Tern I photographed at Stockton Breakwater, Newcastle? I was not birding at the time and had no binocs, just the camera. I just got around to looking at the photos from the day.
.
https://picasaweb.google.com/Roger.Giller/Tern?authkey=Gv1sRgCL-I_52v9pzJjwE #5721219021550844578
Thanks
Roger
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Actually Nikolas I have to admit Ps 4, 8, 9 and 10 look incredibly similarly aged and those outer three just don’t look trashed enough for 2nd year feathers, but I doubt if this scenario has ever been recorded before in any species of Tern assuming it was a correct interpretation. Where has Chris got to.
Cheers Jeff.
Sent: Thursday, 22 March 2012 2:09 AM Cc: ‘Birding-Aus’
G’day Nikolas,
I’m am not aware of it ever being recorded that juvs can moult same generation from two points within the primaries, where as it is known that for Common it is possible for inners to start moulting before outers are complete.
Cheers Jeff.
Sent: Thursday, 22 March 2012 1:41 AM Cc: ‘Birding-Aus’
Hi Jeff,
Why not P1 and P2 fresh 2nd generation, P3 missing?, P4 old old retained juv., P5 and P6 fresh 2nd generation, P7 missing and Ps 8, 9 and 10 old retained juv.?
Also the secondaries look quite dusky, which would fit 1st winter/1st summer better than 2nd winter/2nd summer?
Cheers,
Nikolas
G’day Nikolas,
I’m am not aware of it ever being recorded that juvs can moult same generation from two points within the primaries, where as it is known that for Common it is possible for inners to start moulting before outers are complete.
Cheers Jeff.
Sent: Thursday, 22 March 2012 1:41 AM Cc: ‘Birding-Aus’
Hi Jeff,
Why not P1 and P2 fresh 2nd generation, P3 missing?, P4 old old retained juv., P5 and P6 fresh 2nd generation, P7 missing and Ps 8, 9 and 10 old retained juv.?
Also the secondaries look quite dusky, which would fit 1st winter/1st summer better than 2nd winter/2nd summer?
Cheers,
Nikolas
Hi Jeff,
Why not P1 and P2 fresh 2nd generation, P3 missing?, P4 old old retained juv., P5 and P6 fresh 2nd generation, P7 missing and Ps 8, 9 and 10 old retained juv.? Also the secondaries look quite dusky, which would fit 1st winter/1st summer better than 2nd winter/2nd summer?
Cheers,
Nikolas
Many thanks for interrupting your holiday at Kiama to post these extra images Roger,
There is now no doubt that this bird is a Common and I can now see the wing in these new shots clearly and it leads to a reinterpretation of the originally posted image. But it is still a very interesting individual and I am going to need some input here from Chris here as this bird has two sets of moult going on eg three generations of primaries, so I’m guessing this bird must be into its 3rd calendar year. Haven’t got any photos showing this clearly until now. Going back to the originally posted photo it would now seem that the bird’s left wing has P1 and P2 fresh 3rd generation, P3 missing?, P5 old 2nd generation, Ps 5 and 6 fresh( this was Chris’s assessment) 2nd generation?,P7 missing and Ps 8, 9 and 10 old retained juv. So this bird must have moulted the first 4 primaries last year possible late compared to other same aged birds and then stopped for the rest of the calendar year, need a second opinion Chris.
Cheers Jeff.
Hi Roger,
Thanks for adding these new pictures. I think that the pale new inner primaries (possibly p5-6) in contrast to the old brownish outer primaries (looks like p8-10) in combination with the now even larger-billed, longer-necked, plumper-ended and short-tailed appearance speaks for Common Tern.
Cheers,
Nikolas
Hi guys,
Firstly let me thank you all for your efforts and the interesting discussion on this Tern I.D. No wonder I was struggling to identify it just by looking in a couple of field guides! I have added three more images to the album. They were shot in RAW and I have just cropped them and saved as a maximum quality JPEG. I looked at my images of the roosting birds but they are all Crested Terns.
I have made some measurements of the bill length compared to the bill tip to eye distance from my photos and similarly for a few on-line images of Arctic Terns and Common Terns. The results were: Arctic Tern 58-63%, Common Tern 68-73%, my Tern 72%.
My vote goes to Common Tern, but I’m happy to be corrected if the feathers tell a different story.
Regards. Roger.
G’day Chris,
I agree with everyone, the general look is Common which is why it took me a couple of days to raise these questions, eg long body and neck, and longish bill, although that bill does look rather sharply tapered. I was just concerned about those primary tips and I am still concerned because I can’t identify a clean set of four Ps behind them, the secondary/primary junction is discernable. This is why I am keen to see more images so I can put to rest if this is the birds maintained appearance across multiple images, and hopefully shed more light on those primaries. If nothing else I am about to learn more about 1st year Common Tern. Moult stage is generally OK for 1st year of either species.
Cheers Jeff.
Hi all
I’m guessing that’s P5 and P6. Look at the relative positions of the tips and think how many more Ps you could fit beyond them. Also, if P3 and 4, I’d expect to see white on the inner webs near the tip in either species. I think that probably is P4 you can see on the right wing.
Given the extreme backlighting, I’m not surprised to see that much translucency on a Common, and the new primaries actually don’t show much hint of it, which is not great for Arctic.
It has long been my impression that Common’s show a much narrower dark trailing edge when the feathers are fresh. I think that’s because the feathers darken initially at the tips where the wear is greater. You can see how the longer new P shows a clear gradation of darkness towards the tip, which is not what you would see in an older feather.
The jizz is much better for Common, with that rangy neck and fat rear body, and the head pattern is so typical, with that almost isolated eyepatch.
Cheers, Chris.
G’day Nikolas,
I can see what you mean and my initial response was also Common, but a more considered look the following day focused in on those fresh primaries they are a problem looking like that at Ps 3 and 4, is the dark tips real or an illusion and are they really Ps 3 and 4, also I would prefer them to be more solidly dark but this is a 1st year bird no matter which species.
Is the bill just too long for an Arctic and outside possibility, I’m not sure, it certainly looks rather sharply tapered but I agree it does seem a tad long. Some more photos will reveal if this is the only shot of it looking long bodied or not. The thing to note is that this bird is in Sydney and not at either of the poles so it might influence body volume.
Thought we shouldn’t be too quick on this individual without seeing more images, would like to hear opinions on those two fresh primaries.
Cheers Jeff.
Sent: Wednesday, 21 March 2012 2:10 PM
Hi Jeff & Roger,
Yes, it is worth to have a look at more pictures. Would be nice to see the upperparts, too.
To me it looks too heavy-billed and long-necked for a classic Arctic Tern. Also I thought that the dark trailing edge of the wing (i.e. tips of p3/p4 in this case) is too diffuse for an Arctic Tern. Do you think the secondaries are translucent enough for Arctic? What about the dark grey outer rectrices?
Just a quick thought. Don’t have my ornithological literature here at work.
Cheers,
Nikolas
Hi Jeff & Roger,
Yes, it is worth to have a look at more pictures. Would be nice to see the upperparts, too. To me it looks too heavy-billed and long-necked for a classic Arctic Tern. Also I thought that the dark trailing edge of the wing (i.e. tips of p3/p4 in this case) is too diffuse for an Arctic Tern. Do you think the secondaries are translucent enough for Arctic? What about the dark grey outer rectrices?
Just a quick thought. Don’t have my ornithological literature here at work.
Cheers,
Nikolas
I’m wondering if we can discount this bird as a possible 1st year Arctic Tern. The left wing is in a really bad way with a big chunk of primaries missing in the middle. I strongly suspect that the two fresh primaries that appear to show narrow dark tips are primaries 3 and 4, if that was the case it is problematic for Common which typically doesn’t show dark tips until around primary 5. Note also how transluscent the wing is, and how the dark tips don’t feed onto the leading vein of the feathers. Admittedly the wing is rather compromised however but I thought that Arctic may be worth considering. Have you got any more images of this bird Roger, no matter about image quality.
Cheers Jeff.
It’s a first year Common Tern, a bit less than a year old.
Cheers, Chris.
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