There is an interesting discussion over at rec.guns about the best way to deal with a squirrel chewing on the roof. It is worth a read.

“Pumper Hinkle” sums up the options:

Hmmm. I understand your problem better now. For the squirrel to be
chewing on your roof, though, he must be sitting still for at least a
little bit.

I believe that if it were happening to me, I’d get a night vision scope for
the bolt-action .22 and sight it in using BB caps. I’d then set up a
sniper position and be patient. Once it stands still, bang.

Or, well, you could get a .410 shotgun and some light loads, and figguring
on patching the roof maybe.

Or, I believe you can fire .45 colt cartridges in a .410 shotgun, and I
believe you can get .45 snake loads.

As you’ve observed, the .22 snakeloads don’t cycle in autos, and the rifling
disperses the shot too much. I believe I once heard of a smoothbore .22,
which would give better range.

But I assume you don’t want to buy another gun, especially some sort of
specialty gun. So, back to first suggestion, night vision scope on the
.22.