I have one who lives in my backyard. I see him every day. Didn’t realize this was such a big deal.
Start taking pictures
It’s not a big deal. I have several in my neighborhood. And totally black grey squirrels.
I see a lot of animals, (big and small), cruising around the woods up here but I have never seen a white squirrel.
There are three that visit our bird feeder every day. 3/4 of mile down the road there’s another colony of 1/2 dozen or so.
Saw one in Marietta Georgia about 8-10 years ago. Never seen one since.
They are so highly visible to predators (except in snow) that few probably reach maturity.