Revisiting possible white-winged tern photos (1 Viewer)

[Earnest lad]

A few months ago I posted some young marsh tern photos taken in 2019 (September) at Shabla Tuzla Lake while on a vacation to Bulgaria.
Several people responded helpfully with the birds' possible identification, including Alexander, who helpfully drew my attention to the dark "saddle" on the upperparts, which indicate probable White-winged Tern.
I did tick these off after this as a lifer species.
However, recently I have noticed the dark shoulder "peg" as seen and arrowed in the photos here, and now I am puzzled. According to what I have seen written the dark "peg" should be abent in White-winged tern. However the "saddle" seems to be pronounced, and one would have thought the presence of the saddle would rule out black tern and whiskered Tern.
In view of this I would be grateful if please, could anyone who has more than my very limited knowledge and experience of childonias terns be able to provide any comments or advice.
Thank you.

 

[01101001]

Collins says that juvenile Black Terns with a darker-than-usual saddle and lighter-than-usual rump are pitfalls for White-winged Tern juveniles. The black shoulder mark should make it a Black Tern? Maybe the bill length/shape in the first picture could also provide a clue?

 

[Steve Lister]

Black Tern for me.

 

[Earnest lad]

Collins says that juvenile Black Terns with a darker-than-usual saddle and lighter-than-usual rump are pitfalls for White-winged Tern juveniles. The black shoulder mark should make it a Black Tern? Maybe the bill length/shape in the first picture could also provide a clue?

Thank you. I couldnt decide regarding the bill length and shape, as I have not much real life experience and the bill is foreshortened due to angle. It is a pity the rump in not in view. I may reluctantly have to leave this one as a "possible."

 

[Earnest lad]

Black Tern for me.

Thank you for your input LOL

 

[01101001]

I can't say anything certain about the bill as well, but the arm mark alone should be definitive as far as the three Chlidonias terns go?

 

[01101001]

I can't say anything certain about the bill as well, but the arm mark alone should be definitive as far as the three Chlidonias terns go?

black shoulder mark = definitely not juv. White-winged Tern, probably not juv. Whiskered Tern
solid dark saddle = definitely not juv. Whiskered Tern
=> juv. Black Tern from what I'm being told

 

[Earnest lad]

I can't say anything certain about the bill as well, but the arm mark alone should be definitive as far as the three Chlidonias terns go?

Thank you so much. I havent seen a single photo of white winged tern on google search that has the arm mark.

 

[Alexander Stöhr]

Hello,

thanks for bringing this interesting bird up again, especially if you have doubts.
I must admit, I am still in the White-winged Tern camp here, by rounded head with steep forehead and head pattern (much white above eye and large white area behind the dark mask, making the mask look like a vertical bar=head phone in the ID guides, and some paler mottling on the crown???).

Therefore the head looked (and still looks) like an ID-book White-winged Tern. And yes, although difficult to judge with confidence, the bill looks dainty imo, adding to the White-winged Tern. head impression.

I cant remember having seen a Black Tern with such an White-winged Tern like head before. But I havent seen enough 1cy White-winged Terns to give an confident answer here, so I am glad for correction Steve and 01101001 you know.

 

[01101001]

I was only ticking off boxes as per the field guide--no in-the-field experience with seperating the pair yet. How long, relatively, are the legs in these pictures? It somehow eluded me that this particular bird was discussed already.

 

[Earnest lad]

Hello,

thanks for bringing this interesting bird up again, especially if you have doubts.
I must admit, I am still in the White-winged Tern camp here, by rounded head with steep forehead and head pattern (much white above eye and large white area behind the dark mask, making the mask look like a vertical bar=head phone in the ID guides, and some paler mottling on the crown???).

Therefore the head looked (and still looks) like an ID-book White-winged Tern. And yes, although difficult to judge with confidence, the bill looks dainty imo, adding to the White-winged Tern. head impression.

I cant remember having seen a Black Tern with such an White-winged Tern like head before. But I havent seen enough 1cy White-winged Terns to give an confident answer here, so I am glad for correction Steve and 01101001 you know.

Thank you so muh for this helpful response. The id head details provided are hitherto unknown to me so I will study these too. For now I think I will put it down as a "possible" WWT, but, if and when later on my knowledge and experience increase I may revisit these photos again at a a later date with who knows, more confidence to upgrade the sighting to "cert". LOL, and I have full respect for others' expressions about it because it is clear all these are more knowledgeable than myself.