15 September 2015

Confusing Plumage on a 1st/2nd Cycle Type Herring

This past weekend Alvaro Jaramillo and I found this Herring Gull on the Saginaw River in Bay City, Michigan (13 September 2015):

Scapulars could pass for a retarded 2nd cycle, as well as the tertials. But the outer primaries appear pointy.
Note the tips to P6 and P5 are dark gray (adjacent to the tertials). These feathers were not grown at the same time as the outer primaries. See below.

Overall, the plumage looks more like a 1st cycle, but P5-P6 are confusing, as are the outer greater secondary coverts.

Three of the central tail feathers appear to be from a different molt.
A close up of the above image. Beside the 3 central tail feathers that show notable contrast and worn tips, a few of  the lower scapulars have marbled tips and aren't from the same generation as the scaps with notched edges.

Pointed outer primaries and 2 rounded primaries (P5, P6). The wing linings and axillaries resemble a 1st cycle.

I've seen retarded 2nd cycle Herrings, but this one would be pushing the limits. On the other hand, it's hard to imagine the oddities with P5-P6 and the inner rectrices on a HY bird.

EDIT: Thanks to useful comments by Mars Mussee, I've been reassured this is a hatch year bird. 

I'd love to hear of a hypothesis for the two newer primaries on the left wing, and the 3 older rectrices.

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