Make sure all your pack pockets are open when it is left out for the night. I've left this and that in those pockets over the years and the worst that has happened is there are a few ziplocks that have been chewed through.
If you leave anything out at Trail Camp for any length of time, it will disappear. I lost a gallon ziplock with all my breakfast food the only time I camped at TC.
If there's no food in backpack can I leave my backpack inside tent with me? You said they just take gear, makes me not want to leave any thing outside. Makes my blood boil....
Your pack has an odor of food plus it is salt encrusted from sweat, which will lure the marmots. The only time I bring my pack inside is when it rains...and only then because I have a single wall tent.
You seemed freaked by this. I've never had marmots chew through anything valuable in 15 years of Sierra backpacking.
