Is there cougar risk?
The chance of attack by cougar is miniscule compared with bear.
The chance to see a puma is tiny too, though it is getting much more common. We heard tale that the townsite of Waterton once saw 5 cougars at one time coming after the resident mule deer population. A cougar killed & ate a deer outside the restaurant window of the Kilmorey Lodge!
If you are approached by a cougar, be aggressive making noise & waving your arms. If attacked, fight back as if your life depends on it. It does.
Storing food safely
At night you must cache food out of reach of bears & rodents. You normally hang food in bags we use bird-proof kayak bags on metal posts.
Keeping candy wrappers, toothpaste & anything else sweet or aromatic is an invitation to critters.
Many Glacier & Granite Park campgrounds have metal bear lockers.
We also used a bear vault in 2005 as they use in Yosemite. Heavier, but very convenient.
Are there any dangerous snakes?
None we are aware of.