Odd question

[PeaFan]

I checked on my birds around 4am (just the time I wake up to take the dogs out) and they were both (cock/hen) off their perch and on the ground in the dark. There were lots of feathers all over, from the hen. I am guessing from underneath because she has no bald spots visible. First thing I checked for was an intruder, none. They are penned and it does not appear anything got in. They were not agitated or upset and she seems fine. He has been following her around all day, not bothering her but following close by.
Any ideas? Could something have spooked them and maybe got down off the perch? An owl maybe? A yard rat? I can’t figure out the feathers though.

 

[BirdsBeesTrees]

They are probably molting.