Herring Gulls look a lot like the more common Ring-billed Gull. Immatures have a ring on the bill so this is not a fool proof identification aid. The best identification key is size. Ring-bills average about 17.5 inches in length. For Herring Gulls it is about 25 inches. We had both this morning at Marie Curtis park.
The Magic of Birdwatching in Ontario’s Algonquin Provincial Park – The New York Times
In winter I get up at night
And dress by yellow candle-light.
In summer, quite the other way,
I have to go to bed by day. – Robert Louis Stevenson (1850–1894)