The Goose is a registered Trademark of Air Canada, thats the official position.
If you wanted to use the goose, you could use it if you changed it a bit. All you would have to do it add an eye to the goose and maybe change the colour, and legally it would not be a problem, although I'm sure AC would find a way to get it struck down.
"Clive Beddoe says he favours competition, but his actions do not support that idea." Robert Milton - CEO Air Canada