16 December 2017

Advanced Rectrices in 2nd Cycle Lesser Black-backed Gulls

Four advanced, white, tail feathers on an otherwise typical 2nd cycle Lesser Black-backed.
Kenosha County, Wisconsin. 10 December 2017.

The above bird from last weekend has inspired this post. The mismatch in tail-feather pattern doesn't seem to be too uncommon in this age group. I do wonder if these are 3rd generation feathers contained in the 2nd molt cycle (via an extensive prealternate molt). 

Here are a few more individuals from east-central Florida to chew over.


Bird #1 - Volusia County, Florida. 23 Jan 2015.



Bird #2 - Brevard County, Florida. 26 January 2015.



Bird #3 - Brevard County, Florida. 24 January 2016.


Bird #4 - Brevard County, Florida. 26 January 2017.

Appears to be in active molt.