This is interesting. Time out where are you, just sent him a text he should be along shortly lol...
I have a person around the road and she has rats in with her rabbit , she sees them on a motion camera, they are clearly trap shy, she gets the odd rat every now and then which I suspect is a new rat into the area or a juvenile ? If it is a rat it may be wary of the trap after seeing his mate get the bad news ? I dont know about the blood scaring off another rat. I would change the location of the trap by 5m and change the bait to nutella or some chocolate based lure, mix it up a bit.
I would also put peanut butter on your mouse trap.
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