I love that 1st photo of Bo where he's cocking his head at you.
What a beauteous boy!!! Yes, gators can climb chain link fences but I think that's a pretty rare occurrence and they have to have a reason. They might do it for a little dog but still...... However, I don't think they'd want to take on a dog the size of Bo. And as you say, you're a fussy golden mama & he isn't out without supervision and you check around first anyway.
I saw a male cardinal at our birdbath today & he was molting. He had lost his crest. He looked so silly with no crest and he had a bare ring around his neck. Weird.