I murdered every last one of them with sneak attacks by dropping bananas to lead them to secluded corners where I could dispatch them without notice. As the area became progressively more depopulated, I began to lead them on increasingly long and silly bananapaths until finally ending their lives, because I find their sneak/snatch animations to be utterly hilarious. Oh and one of them I killed by putting an octo balloon on a banana and killing the guard when he came to take it.