In other news, here is a hazard of low spoke count wheels and carbon forks you might not have anticipated. A rider reported to be going 20-30 miles per hour caught a squirrel in his front wheel, snapping the fork.
Searching on the topic, I found a number of reports of similar incidents dating back a number of years. One even made reference to snapping a metal fork, in case any steel-frame aficionados want to feel smug. However, the reference did not say whether the "metal" fork might have been aluminum.
Wheels with a higher spoke count would fence out the unfortunate rodents.
Looking up squirrel recipes for a coworker who was complaining about having to go to the grocery store so often, I did discover that large males are notoriously tough. Perhaps young and female squirrels will squish through the forks more easily, causing less damage. Learn to identify the sex of any squirrels you see loitering on the roadside to help you decide whether you should slow down. Also, if you have wheels with heavy bladed spokes, like Mavic's, file them down to a razor edge to slice and dice any squirrels that might enter your wheel. Squirrel confetti might cause a gory splatter, but it's better than using yourself as the human crayon across the pavement. It also kills the squirrel more mercifully quickly.
Thin round or bladed spokes just leave you at the mercy of any animal that will fit through those giant spaces.
Research is underway to determine the minimum spoke count needed to block out your more common roadside fauna. Meanwhile, try sticking cards or aluminum pie plates in your spokes or sticking owl figures on your bike to deter them.
Good luck out there.
Our condolences go out to the families of the squirrels.