Smart dog. You know that some kind of rodent is in there and he doesn't like anything messing with his stacks
If puppydog leans over any farther, he'll fall ovah. Maybe he's thinkin' the closer he gets, the better shot he's got at whatever's in there.
I have 3 cats in the garage that hang out on the wood rack and sit motionless for hours waiting for a mouse Great hunters.