Thursday's Victoria Birding Highlights

I had an unremarkable trawl around the woodland trail in Victoria's Government House grounds yesterday morning. The day started out very warm, and early dragonflies were busily hunting, but bird activity was pretty minimal. The regular residents (downy woodpecker, Anna's hummingbird, red-breasted nuthatch, bushtit etc) were all going about business as usual, but other than a couple of rufous hummingbirds there were no signs of migrants moving through.
In the evening, I headed down to Oak Bay Marina for a scout around. Aimed with 'scope, I was able to scan the offshore rocky islet that seems so attractive to roosting shorebirds, and I was able to count 78 black-bellied plover. Among them were at least 3 dowitchers and one each of surfbird and black turnstone. Around half a dozen Heermann's gulls were on the island too, while a further 40+ were snoozing on another larger rock further out.
Closer, in the harbour area were 3 western sandpipers, a killdeer and a couple of black oystercatchers. The group of 7 greater yellowlegs were again roosting on the same small islet as they were the previous day, along with another pair of oystercatchers.

I made my way over to Clover Point, where despite the human and canine activity, there were still a few birds about.
It was quiet offshore, but there were a few interesting gulls roosting on the nearby rocks to scrutinize.
Among these was a very convincing western-type hybrid, and a 1st year bird that I think might have been a ring-billed gull.

I've included some, unfortunately poor, shots here for you to see.
It was obviously smaller than the California gulls it was among, and something about it didn't seem quite right for mew gull.

The weight of the bill, the overall paleness, and the 'spottiness' all seemed to suggest ring-billed to me... or am I missing something really obvious and making a silly blunder?
Advice and comments from those with greater experience of both mew and ring-billed gulls at this age would be most welcome!