30 July 2018

7th Cycle Great Lakes Herring Gull

Below are images of another known-age, known-origin, American Herring Gull that I found in Milwaukee, Wisconsin over the weekend. It's undergoing its 7th prebasic molt.

Federal Band #: 1106-19241. Banded as pullus on 15 June 2011 in Egg Harbor, Wisconsin (Door County).

Most interesting about this bird is that it shows a p9 mirror on what is presumably a 6th generation primary. Two mirrors on Great Lakes Herrings is, in my estimate, found in only 10-15% of adults, at best.