That's what I was thinking, if there is enough room the lower ranking hens could always find a spot where they could eat in relative peace. Hmm, sudden left field idea, could the boards be bonded together using Epoxy?
And what about the surface of the wood? Should I paint/cover it with something to prevent mold or rot?
I wouldn't...the FF will likely strip any paint or adhesive right off with time, so just making sure it drains well and isn't wet all the time seems to be enough.