M.
Well, I don't know about humanely, but my hubby was told by a rat exterminator to buy a rat zapper and lure it to go into it. It took a few days of the rat trusting and seeing the device there, but when he went in, he was zapped immediately and discarded quickly. Humane? Maybe not...but mice and rat droppings can be dangerous if inhaled/ingested, so they aren't worth the risk to family...just get rid of it.