Pls help ID Terns (3) Greece (1 Viewer)

[geopap]

I take the photo 30/8/07 Northern Greece Axios Delta
I am not sure if all of them are Gull-billed Tern or some of them are White-winged Tern.
Thanks for your help

 

[gerdwichers8]

You have got some Whiskered Terns there.

 

[JANJ]

H i geopap.

The obvious dark breats patch on the first Chlidonias tern (wich they all are) belongs to Black Tern - as is the second one also due to little contrast between mantle and upperwing. Tail looks dark and grey rump (whitish area at the base could be a light efffect or for real) the long bill looks good for Black -all characters compared to White-winged Black Tern.

The third one is a juvenile Whiskered Tern as are the two standing birds in image 4 and 5. The bird in image 5 might have a stout bill (Gull-billed like) but the dark markings on underparts are the remaning feathers from the summer plumage.

http://www.tarsiger.com/gallery/ind...&order=lisays_paiva+DESC&sel=&sel=2&sel=&sel=

http://www.tarsiger.com/gallery/ind...&order=lisays_paiva+DESC&sel=&sel=2&sel=&sel=

JanJ

 

[CAU]

H i geopap.

The obvious dark breats patch on the first Chlidonias tern (wich they all are) belongs to Black Tern - as is the second one also due to little contrast between mantle and upperwing. Tail looks dark and grey rump (whitish area at the base could be a light efffect or for real) the long bill looks good for Black -all characters compared to White-winged Black Tern.

The third one is a juvenile Whiskered Tern as are the two standing birds in image 4 and 5. The bird in image 5 might have a stout bill (Gull-billed like) but the dark markings on underparts are the remaning feathers from the summer plumage.

JanJ

I agree completely. The 1st and 2nd pics show a Black Tern and the rest are Whiskered Terns.

 

[gerdwichers8]

I can't agree completely since the first bird; photgraphed in the first two pictures shows a white rump; I can't make out whether it is overexposed or not.
Since the breastpatch is quite solid, I find it a heavy argument for Black Tern and am aware of the fact that Whiskered shows a slight breast patch; perhaps too weak for this bird.

 

[CAU]

I can't agree completely since the first bird; photgraphed in the first two pictures shows a white rump; I can't make out whether it is overexposed or not.
Since the breastpatch is quite solid, I find it a heavy argument for Black Tern and am aware of the fact that Whiskered shows a slight breast patch; perhaps too weak for this bird.

Black Terns sometimes have whitish rumps (you can check it for example in Mullarney et al.) and yes, the pictures are also partially overexposed (the conditions were clearly pretty contrasty). I do think that the breast patch visible in pic 1 is too clear for Whiskered. Additionally, the primaries are dark grey and the shape of the cap fits better Black. In pic 2 you can see the dark leading edge to the wing, which is at least untypical for Whiskered. Also in that picture the cap fits better Black and the whole upperside of the wing is dark grey (and the bill looks long and thin).

Edit: Well, the primary colour in pic 1 and the bill structure (in both pics) aren't actually especially good id-features in this case due to the quality of the pics, but I think that the rest of the features I mentioned are pretty relevant.

 

[ody]

I was with geopap there.
I id the last one as Gull-billed Tern.
I don't want to confuse you but maybe help with some more pics.

 

[ody]

Here some more

 

[ody]

And also this one I id in the field and later as a GB Tern!

 

[CAU]

Hello Ody! All your pictures are of Whiskered Terns. A Gull-billed Tern is a very large tern, about as big as a Black-headed Gull. A Whiskered Tern is much smaller than a Black-headed Gull, as can clearly be seen from the pictures. Also Gull-billed Terns always have clean white undersides, while Whiskered Terns have dark grey undersides in summer plumage and white undersides in winter plumage (your birds are moulting from summer plumage to winter plumage, therefore many of them still have dark feathers left).

 

[JANJ]

Check head and bill size/shape and as CAU say´s

http://www.pbase.com/clive_temple/image/67750359

http://photography-on-the.net/forum/showthread.php?t=326944

JanJ

 

[ody]

Thank you very much!It was the first time I saw a GB Tern! I id it as a GB Tern because of the black leggs and the black bill. Now I see the diffrnences.
Field work ... hard work...!!!!

 

[lou salomon]

cau, jan, don't you think it is an adult? (at least the last one). it has some 'dirty' moult marks on body, but with such a complete black cap?

 

[JANJ]

Hi Lou.
If you mean my comment on the first section on image 4 + 5, yes, that came out a bit wrong - I meant adults of course. Thank you for reminding me.

JanJ

 

[CAU]

Precisely (didn't first even notice the strange formulation).