I am trying to work on my major bird id weaknesses, for example, gulls... I took this photo today at the local drying beds. I believe that there are two kinds of gulls here. One kind is Bonaparte's and the larger one is Herring Gull????? Am I close?
Points to look for:
1 size - these are just slightly larger than the Bony's; Herring is substantially larger (looks about twice the size of a Bony's) and bulkier, with a 'meaner' face.
2 leg colour - yellow on Ring-billed (except on 1st-years), pink on Herring
3 bill pattern - on adults, yellow with a black band on Ring-billed; yellow with a red spot on Herring. Immatures (also with some brown feathering on the back / wings) trickier, 3rd-year Herring can have a yellow bill with black band, but easily told by brown feathering on the back / wings. Herring also has a larger, stouter bill.