It's this stuff. Add says 2x4 but it's slightly smallerThese openings are only 1.75” X 3”? It may be an optical illusion, but those look big enough for a young bobcat to squeeze through. Cats have an amazing ability to squeeze through tight spaces and climb just about anything. I’m also assuming that you have plenty of bobcats in your area. I think Coyotes are out of the equation, while pretty smart, they don’t have the climbing skills and ability to squeeze into those tight spaces. 🤔
Going by your observations, I would assume that whatever is getting in is doing so through the top.
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