Reptiles in unexpected places

In our small shed, one stall is used for storage of lumber from Dad's estate, small equipment, a small boat, tools... You get the idea. I have a stack of cardboard and used some to transport some replacement windows. While sliding cardboard off the stack, I heard a buzzing sound.

First thought - bumble bees.
 (I've had run-ins with these guys before. They attack the face and I'm ugly enough without swelling from bee stings.)

I threw the cardboard to the ground and stood back expecting a swarm to emerge from the rest of the stack in the shed but nothing. The buzzing stopped. Moving the stack again the buzzing returned.

Now my curiosity compelled me to poke around but cautiously. The sound was on the left in an old tarp. Lifting it, I pulled it back to reveal a tail slapping against the tarp which amplified this ~18 inch fox snake:

Looking at me, it flitted its tongue and continued slapping its tail against the tarp. I snapped the picture a bit late to get this shy snake. It tired of my curiosity and started to climb deeper into the tarp.

I need all the help I can get to keep the mouse population down. Those creatures make their way into the tractor engine where they make nests of bales of hay and tend to chew wires for no nutritional value.

I'll keep the snakes.