We live in Ontario and frequent Algonquin / Huntsville area often
Spring.... as said blackflies at their worst
Moose are seen beside the roads throughout the park in spring because they like the salt from the winter roads that has collected in wet areas. Fall is the next best time.
You may travel the park daily for 6 months and never see one however.
There are along with moose, black bear, deer, wolf and mamy small animals in the park. However, chances of seeing anything is slim unless you are in the back country. However we were stopped in traffic and I looked out the window and a bear was sitting about 10ft away, LOL We have had moose and bear pass through our camp at night.
There is not a lot of winter RV sites available. Summer camping, if you want to secure a sight you must book as soon as they are available to be in the new year. If not you will not be able to get a reserved site. First come fill up really fast.
The Muskoka region is a beautiful area, a photographers dream. If you like to hike you are more likely to see wildlife. My brother has lived in the area 15 years and seen 2 moose and 1 bear.
We would definitely suggest you do your homework, reserve all places you would like to stay, then come north and enjoy! If we can give or gather info for you, PM us.