First welcome to the club. I noticed you were new a few days ago I just didnt have anything relevant to add at the time but now that I do nice to have a new member.
I cant say I know a lot of unique to Canada species.
Im not sure if there are other zoos in the US working with Eastern Loggerheaded Shrikes. A couple of Canadian facilities are.
Oh one I can say Vancouver Island Marmots are unique to Canada. There are so few I doubt we would have shipped any to the US. I got to see one in Toronto's health center once. Very cool to be an Ontario resident and be able to see Canada's rarest mammal. Probably one of a very small group outside of keepers to have seen them here because they are not display animals.
While not exclusive to Canada, Moose are pretty flipping rare in North American zoos. The SSP lists just a handful of them. Toronto and Zoo Sauvage have them. Not sure anyone else does.
Big rarity at the zoo though is Lloyd our white headed vulture. There are just 2 in all of North America which is pretty cool. I think they are more common in zoos elsewhere but I will take a North American win.
If you are looking for more of unique in Canada and dont care if other countries have them check out this thread.
Species only found at one zoo or aquarium in Canada?
Sometimes checking out the older threads can provide really cool information.