update on 1st cycle Lesser Black-backed Gull at Davis Landfill pond

Steve Hampton


The other day Lucas Corneliussen, together with Lucas and Mark Stephenson, reported a 1st cycle Lesser Black-backed Gull at the Yolo County Landfill. The photos are here: https://ebird.org/checklist/S80296258
There is also a video. 

I engaged them in a discussion about the id-- my main concerns being the solid tail (in the last photo) and the rather pale upperparts (scaps and back). LC emailed me the video for better viewing than on a phone. This provided some views that clearly showed a banded tail okay for LBBG. We then sent the images and video to Amar Ayyesh, an expert in the East familiar with separating 1st cycle LBBG from Herring-- relatively straight forward at close range but challenging at the distances we are typically dealing with at Yolo Landfill. Amar replied that it looks "pretty good" for LBB, noting the darker greater covert bases, long wings at rest, whitish breast, and tail band. He did have reservations about the paler post-juv scaps. 

I think, based on the video, that the bird was in the smaller water area on the east side of the landfill pond. This can be viewed from the levee above Rd 28H -- and you can walk down across the road right up to the fence. A scope is important. Unfortunately, with a north wind, the gulls are typically at the far north edge of the pond, so I recommend waiting until the wind dies down or turns to the south. 

LBBG has become annual in Yolo County, so a 1st cycle bird is expected-- though difficult to pick out. The adult LBBG is still around, usually sleeping among Calif Gulls in the vicinity of the long diagonal swale that cuts thru the pond. This adult bird is best picked out on an overcast day (when the true mantle colors are easier to discern), when all the birds are facing the same direction, and when you position yourself to be looking sideways at the birds. I've found it in a few minutes under these conditions.   

good birding, 

Steve Hampton
Davis, CA

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