I can respond to that, because you make me think of my own family on my mother's side, which settled in Niagara Falls, Ontario, when they first came to Canada as Jewish immigrants in the late 1800s. My great-grandparents and grandparents were part of the group that founded the Niagara Falls synagogue, but there is no longer a Jewish community in Niagara Falls, or rather, there's not enough people to sponsor a synagogue. The synagogue was shut down long ago. There is still a Jewish cemetery. There are still remnants of Jewish life there.
I think you make a good point. That's just one of many such communities across Canada. Cape Breton is famously also one of them. Preservation of Canadian Jewish history is also a potential focus of this, as is a remembrance of where people settled and the contributions they made, even if they are no longer there in significant numbers. This can also be a rich element of what can be done if prompted by a Jewish heritage month.