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ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

S California coast bird, today (2006-04-16) (1 Viewer)

here an enlargement.
bill appears long and not particularly G-b Tern like

is that wingpattern right?
bill appears dark not black

what other choices are there?

cheers,
housecrow
 

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thanks. the enlargment clearly shows the black feathers to be limited to the top of the head. the bill seems a bit lighter than the black feathers.
 
One note / question; can we tell what is the left wing and what is the tail from this picture? They seem to line up (annoyingly) perfectly, so it's difficult to estimate tail length.
 
overworkedirish said:
One note / question; can we tell what is the left wing and what is the tail from this picture? They seem to line up (annoyingly) perfectly, so it's difficult to estimate tail length.

I don't think wing and tail are in the same line.
If you look at the base of the right wing, at a 90' angle, you see what appears to be the tip of the left wing of the bird.
 
HouseCrow said:
I don't think wing and tail are in the same line.
If you look at the base of the right wing, at a 90' angle, you see what appears to be the tip of the left wing of the bird.

Yes, I see that, but my question was can we tell where the tail ends and the wing begins (the angle lends the two to be lined up)?
 
for a wee bit extra clarity, and to check how my original conversion from raw affect the colors, imported it again from the cameras raw file using the camera's settings. I then enlarged it by about a factor of 4 in 6 steps using cubic interpolation.
 

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Ah! I see now. In that case, not only is the bill too long for Gull-billed Tern, but the tail is too long.
 
my guess is that the top side of left wing tip is visible as the little white triangle at the end of the hand drawn line.

clues in the picture seem to make it certain that the bird's backbone is very close to being parallel with the photographic plane. the near vertical imaginary line between the putative white left wing tip and the right wing tip is consistent with this.

the long black trailing streak is very straight, and perhaps too straight and thin to be an edge view of the distal half of the left wing.
 
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greenerisbetter said:
my guess is that the top side of left wing tip is visible as the little white triangle at the end of the hand drawn line.

clues in the picture seem to make it certain that the bird's backbone is very close to being parallel with the photographic plane. the near vertical imaginary line between the putative white left wing tip and the right wing tip is consistent with this.

the long black trailing streak is very straight, and perhaps too straight and thin to be an edge view of the distal half of the left wing.

Only one species of tern that I know of shows a head and bill structure like that, combined with the dark underside of the primaries.

By the way, I think the long 'tail' is in fact the left hand wing, as has already been suggested. The whitish triangle at the base of the right right is just a stray feather I'm pretty certain.
 
While the color of the bill suggests Gull-billed Tern, the length is wrong. And the amount of dark in the primary feathers are to extensive along the trailing edge of the wing to be this species (In my never to be humble opinion). I think the dark bill is an effect of lighting but the shape suggests CASPIAN TERN or ROYAL TERN.

Gull-billed Tern:

http://www.windowsonnature.com/Natu...ter_Birds/images/BD_Tern_Gull_billed_Flys.jpg

Here's a Royal Tern wing mount I found:

http://www2.ups.edu/biology/museum/ROTEwing22231.jpg
 
The bill is too thin and dull for Caspian Tern or Royal Tern. It is either a Forster's Tern or a Common Tern. Based on location, I would go with Forster's Tern.
 
My comment is I'm baffled. It looks like a small and very pointy tern. if it had a dazzling white underwing I'd be suggesting Roseate tern - but the underwing is all wrong. It even reminds me of a Bridled tern.
 
Dave B said:
Only one species of tern that I know of shows a head and bill structure like that, combined with the dark underside of the primaries.

By the way, I think the long 'tail' is in fact the left hand wing, as has already been suggested. The whitish triangle at the base of the right right is just a stray feather I'm pretty certain.

My earlier comment was intended to lead to the conclusion that this is a Caspian Tern, which is what I think it is!
 
hesitatingly, I'm setting up Bridled camp, anyone care to join me
I googled a bit and:
-the wingpattern could fit
--thin finger of white can be seen (don't know if it really is valid, but MacMillan notes it as distinguishing point)
-some bridleds have tiny white foreheads
-tail of Bridled is extremely long sometimes

contra:
long slender wing seems to point at sooty (or any other small tern)

the fact that it is a review species with only 3 sightings (no photographic evidence) doesn't make it impossible.

have never seen any rarer tern than...Gull-billed so know who's saying this.

cheers,
housecrow
 
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