> They really shouldn’t be let outside unsupervised.

Alternatively, get them a collar with a little bell, and let them try (and always fail) to hunt.

I guess the odd deaf squirrel wasn’t likely to last long anyway. A bell could work to keep them from stalking. They can still run, leap, and ambush. It seems a bell should at least greatly mitigate the issue. I might say usually rather than always. To be fair, though, supervision won’t stop them every time either.