If you don't want the critters such as ringtails, skunks, or bears sniffing your nose or licking your lips and face while sleeping at night do the following:
1) Eat your evening meal somewhere other than at your campsite.
2) Don't eat snacks just before bedding down for the night.
3) And don't brush your teeth with toothpaste as toothpaste will attract the critters.
P.S - and yes ringtails at some of the hardened campsites such as at Phantom Ranch have learned how to unzip your packs but for the most part they will just tear into and destroy a pack to get to the food inside.

A man's body may grow old, but inside his spirit can still be as young and restless as ever.
- Garth McCann from the movie Second Hand Lions
I really am a masked man
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