If I were you, unable or unwilling to kill them, I'd hire a nuisance wildlife person to deal with them. Lots of pest control companies also perform this service. You're just going to temporarily run them off with a pellet gun and if you can't securely block where they're nesting they'll be back in no time. In addition, the babies they undoubtedly have are imprinted on your place as their own territory. Your cat food is their cat food. Your cats are imperiled. Nuke em. A pellet gun is just going to piss them off.

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You're a daisy if you do.
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