18 October 2015

More Thayer's & Lessers

New Buffalo, Michigan. 17 October 2015.

I found my first juvenile Thayer's of the season yesterday - bittersweet looks at a bird that fled almost the second I spotted it. 

There were also 2 adult Thayer's present (bringing my total to 11 distinct Thayer's in the last 2 weeks). Both of the adult types were without P10, a much more typical molt state for our earliest arrivals here on southern Lake Michigan.

Thayer's Gull (center). A relatively pale-eyed individual.

Herring (left) with pale-eyed Thayer's (right).

A darker-eyed bird with a duller bill pattern.

I've stopped counting adult-type Lesser Black-backeds at this point. From here on out, the only adult LBBGs that I count at this site, for the rest of the season, are distinct and obviously "new" arrivals.

Out of the 4 birds present yesterday, a 3rd cycle type and a juvenile were "new" birds that I've not seen this season.

The majority of the Juvenile LBBGs that I see in the Lake Michigan region have broader scapulars with rounded, convex edges. This semi-hollyleaf pattern is not something I often see. Also, the notched tertial tips show patterning that I don't normally get.

Compare the bird above with this one from last weekend in Lake County, Illinois:

Broader and plainer scapular edges, as well as plain tertial tips.

Finally, here's a 7th cycle Herring Gull that was nice enough to allow a full band read:

Band #1106-13208. Banded on 20 June 2009; 7E of Chambers Island. Door County, Wisconsin.
Bill and body size suggest this is a female. 

Meanwhile, I eagerly await our first Iceland & Glaucous Gulls of the season...

Me on New Buffalo Beach reading a Herring band. Photo by Mike Bourdon.

No comments:

Post a Comment