Rats leave droppings everywhere they go frequently so look for the droppings. Daylight won't phase a rat as long as they are in coop where they have some cover from their natural predators.
Start checking your feed usage. A quarter pound of feed per adult hen, ignore the roosters. If you are feeding more than that you are feeding something else.
Start checking your feed usage. A quarter pound of feed per adult hen, ignore the roosters. If you are feeding more than that you are feeding something else.