I don't know much about gar or when they spawn, but I think they're spawning on the rocks.
I was bass fishing yesterday afternoon and hung six but only landed one, I fought it for over an hour, it was daylight when I hung it, and it was dark when I got it to the boat.
It was around four or five ft. long and foul hooked on its back, just behind the dorsal fin. It was like I caught an anvil. If you like catching some big ones, get a rattle trap and fish the 66 rocks on Hubbard.