By this time most years, a Yellow-legged Gull has already put in an appearance. Where is our YL Gull this year?
1) As shown in the first picture, the YLG has a snow white head (and of course, yellow legs) from about mid-December onward.
2) At this time of year (November), the YLG can have streaking on the head and face. The streaking can look darker around the eye. There is never streaking on the breast of the YLG. This streaking will gradually disappear from the back of the head to the front as the month progresses.
3) This third picture is of a Lesser Black-back Gull taken just last week in a parking lot. Because this bird doesn't have any breast streaking and does have extensive head streaking, it is a little more difficult to ID. I would advise looking for the answer to this question on Dave's site. There are actually several reasons he gives.
The best opportunity to see one of these special gulls may be around Quidi Vidi Lake, where (in the past) they have been spotted on the water as well as in the surrounding area including rooftops (like Santa) and ball fields. Keep hunting as there may just be a rare gull around already!