Just a bucket wouldn't be protected enough.
When I was young we would go pick nightcrawlers from a couple different places for fishing the next day. We would go probably once every week. Any worms we didn't use we would dump out that evening on our lawn or in the garden. The next year, we hunted on our lawn without any problem. If we wanted worms, we would set the sprinkler out right about dusk and let it run for a while, maybe an hour and turn it off and go out hunting. I remember grabbing some that I would see at the corner of the light and immediately dropping them because they were so big I thought it was a snake, not a worm. We literally got some that compressed were thicker than my thumb and approaching a foot long. Stretched they would be over two feet and when we put them on worm hooks for trout we would have to pinch off some of the bigger ones into 4 pieces to even get them all onto a hook.