Reason why I'm back into airgunning

I been taking care of these critters for about 3 years, but since they live in my chicken coop with shelter and food is almost impossible to get totally rid of them.
just trying to thin them out a little.
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I used my hw35 in .177 Cal. @14 yards using a red light cause these guys comes out at night only. I took a head shot because that's the only part of his body I could see, but with this kind of mouse I can take body shots as well with devastating results due to their fragile body, they only measure around 2" but their droppings cause sickness​ in my chickens