Tuesday, 11 February 2014

American herring Gull - Part II

Some snapshots taken from 720p video at 120x with the digiscoping method. There are a few strange dark marks and lines on the snaps but they are no more than debris and dust particules in the camera due to heavy field work..... this little girl have a few miles of it!

On the above and below photo, note the heavy structure with squarish and flat head, pencil shaped bill reminescent of Caspian Gull Larus cachinnans and colored like winter adult Glaucous Gull Larus hyperboreus. The winter head steaking is also restricted to the hindneck and mantle color, although hard to evaluate was paler than any ssp. argenteus I have ever seen, matching Ring-billed Gull Larus delawarensis and always distinct from the nearby Yellow-legged Gull Larus michahellis.

On the sequence below note the primary pattern with a few good indicators for American Herring Gull.

From left to right:
1. Visible "bayonet" on P7
2. Visible "bayonet" on P7 and "W" shaped dark band on P5 tip
3. Pattern on P10
4. Pattern on P10
5. Visible "bayonet" on P7, "W" shaped dark band on P5 tip and long pale tongue on P8
6. Pattern on P10
7. P9 pattern and long pale tongue on P8. Black fine line on P10 tip
8. Pattern on P10
9. Pattern on P10
10. Pale tongues on most primaries
11. Pattern on P10
12. Black fine line on P10 tip

Note how the angle of the pale P10 tongue ends in several snaps. It seems to be variable, but the steeply curve on it seems to be intensified by the pattern of the P9 behind.




On most aspects its seems to fit perfectly on American Herring Gull Larus smithsonianus, and a few experts on the species agree with the identification...

Now let the 2 and 3cy come!!!!!

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