Cut mouse hide off of dead mouse. Glue to egg shaped foam. Epoxy taxidermy mouse onto big hook - Mouse Fly! What'd be more realistic a fly than a real, dead, stuffed mouse on the hook? The only good mouse is a dead one. Or a PC mouse.
We discovered last year a couple months after moving in to our place - that there were holes leading from the foundation into the utility room of our place. We had a LOT of snakes and mice hanging out - I had to plug the holes up w/ foam cuz our property managers wouldn't do jack. "It's just mice and garter snakes, right?" HA!
At one point we had at least a dozen garter snakes living in the cracks in our front porch (cement) and under it. I saw the slithery little bastids go into vent holes in the foundation. While we thankfully haven't found any snakes in the house yet - I killed half a dozen mice in three days when I started my war against vermin kind last year. Traps, bait, and at one point stepping out of the shower - I had a mouse come out of the heating vent into the bathroom and whacked it with a baby louisville slugger.
If we lived where there were rattlers and had that issue, I think I would've had no other option than ten gallons of gas and a road flare - the closest thing to a tactical nuke I can afford.
Good luck on the trip!