Riding Mountain National Park has a lot of hikes. This fall hike took us to a beaver dam.
For a while, when the anti-fur lobby was at its peak and no one was wearing furs, trapping of beaver stopped, and the big rodents were everywhere in Manitoba -- cutting down every deciduous tree within any distance to any river/lake. This was especially frustrating if you were a cottage owner who planted a weeping willow the year before.
Close to Wasagaming in Riding Mountain National Park is the Omnick Marsh hike. It is a good place to try and sneek up on ducks, etc.
There are a fair number of interesting hikes to try out in Riding Mountain. One is Bead Lakes. I think it is half way up the park on Hwy # 10.