Do I have a squirrel infestation?

I found this in the trunk of my PC800 yesterday when I was getting ready to go for a ride.  Last fall I found a couple similar pieces of dog food and I thought “oh one of my friends must have had some on the bottom of their bag…”

Well this time I found about a cup worth.  The bike had been sitting for about two weeks due to bad weather and school.  I know there wasn’t all of this in there before I parked it.  How in the world could an animal be getting into the trunk to put all this in there?  I hope they aren’t chewing on any wires or hoses!