I have three 18-week-old Khaki Campbell ducks. They should begin laying in the next couple of weeks, and I'm wondering what I should provide for them to lay in. Just a box with hay in it on the ground? I have a smaller area in their hut that I thought would be a laying area, but now it turns out they've all been sleeping in there, so I don't want them to crush the eggs. Any suggestions of what to provide for them?