Early July feature Canada day weekend with crowds while early September features Labour day weekend with crowds so a draw there.
Have been in the Canadian Maritimes for both weekends and it's not much different than here. However, the civic holiday that falls in August is a completely different story. It's the only time we ever left Fundy National Park early (we used to visit there often).
Are you worried about having an altercation with an animal ?? Or more so that you would rather see the wildlife while their young are still small ?
Not worried about altercations. I prefer to see babies, guys prefer large racks. (Please keep your thoughts clean-this is a family forum!! :B)
"Seeing" wildlife is one of the huge attractions to visiting the Canadian Rockies. You will absolutely see Elk (probably every day) and deer, and likely a few black bears. If you are lucky you might see a Moose. If you leave them alone (i.e.. keep your distance and respect their space) they will leave you alone.
We're very experienced in dealing with wildlife so no worries there. During our first visit to Banff/Jasper we saw the awesome sight of elk forging one of the rivers as well as shared a campground in Jasper with part of an elk herd. Saw lots and lots of different animals and that's one of the reasons we are going back. Our son hasn't been there yet and this is actually his suggestion. We had already starting planning a trip to Cayman Island and had hoped to go to the island in May then AB late summer; unfortunately the travel budget can't handle both (flying gets expensive) so we've chosen 10 days in AB and then just an extended long weekend in Bar Harbor, ME.