Carpentersville Dam – 12/21/2016


Target species : Barrow’s Goldeneye, Lesser Black-backed GullThayer’s GullIceland Gull

Unexpected birds : 26 Bald Eagles, leucistic Common Goldeneye, and 2nd year Iceland Gull (not the regularly seen 1st year)

We started the day off at the Otto parking lot. There we found ten Eagles in one tree and eleven others flying around and hundreds of Canada Geese in the water. After that, we drove up to the dam finding lots of Gulls. After some scanning, we found out that the Herring Gulls way outnumbered the Ring-billed Gulls. In that flock, we found a juvenile Thayer’s followed by an adult. Shortly after we found those, we found an adult Lesser-backed Gull (first of season for me). Then Brendon Lake showed up and we pointed out to him the Lesser Black-backed. We also found a borderline 1st winter Herring/Thayer’s. We were still missing the Iceland Gull. After some searching though, we found one (but not the same one as seen previously). This one was a 2nd winter with a bicolored bill. Then we headed down the path to scan the other side of the waterfowl that we saw at Otto. Once we got to a good location to observe them, we found a flock of about 80 Common Goldeneye. We searched for the Barrow’s with no luck but we did find a very interesting looking leucistic Common.

UPDATE : The 2nd year Iceland Gull was Identified as a Herring x Glaucous Gull Hybrid


Published by Oliver Burrus


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