In that situation, I would just pen them until I get back from riding. Like I said, we get paranoid.
I am starting to lean toward free ranging myself. Right now we use some temporary fencing to section parts of the yard we want them to stay in. I have one culprit though, that regularly jumps...
That is a choice you must make for your lifestyle. Personally, I wouldn't leave them unattended until they are mixed in with a larger flock. And even then, we get paranoid so we don't free range the larger birds ( ducks and chickens ) when we aren't home. We lock them in their run.
Do you have...