Be aware of lots of mosquitos, Banff National Park
In summer, there seem to be a lot of mosquitos, especially on the campgrounds. You should wear a net over your face, to be protected of mosquito bites. West nil virus is spreading more and more in this area! On some campgrounds (especially Porcupine and Lake Magog Campground) it was even impossible to leave the tent!
I'm of course referring to the swarms of ravenous mosquitoes that patrol open areas. They were so numerous that they blocked out the sun. Okay, so it was a little exaggeration. But the mosquitoes were so tenacious that they'd stick around, literally, until they become so overly engorged that they fall off on their own, or until a well-placed backhand temporarily provides respite. I was never more afraid of West Nile virus in my life!