I know this game, and have played before.
A ‘teenager’ swims over with purpose, not a random wander over. If you are a) a smaller gator you leave, or b) a new human you back up. Either way the prime location opens up.
Along this part of the bank there are some nice dry, and easy access, spots to sleep. They do it all the time.
What is really funny is when a person stays and hangs around there. The Alligator turns and slowly goes off. Just wait… he will casual swim by, checking the spot. Sooner or later he gets it.