[EBB Sightings] Unusually colored Western Gull at Lake Merritt

Below is a link to photos of an Western Gull near the duck pond at Lake 
Merritt with very vibrant orange bill and legs.   According to Alvaro 
Jaramillo it is a phenomena he sees in a few birds every spring tied to 
breeding season so it suggests that it is the hormones that kick in on 
overdrive on some birds.  There are also a couple photos with "regular" 
Westerns to see the difference.  My first reaction was to consider other 
gull species including Yellow-footed.  But according to Alvaro, in 
comparison with Yellow-footed Gulls the differences include: Western paler 
backed; bill extensively orange, not the typical banana yellow; legs yellow 
but feet pink, or at least webs  pink while these are yellow on 
Yellow-footed Gulls.

http://bethb.smugmug.com/Birds/Lake-Merritt-Gull/11444341_MTCZz#804681066_uAZL6

Beth Branthaver