I had a nightmare with rats a few years ago. The neighbor's coop inside was always covered with loose feed. It was awful. I tried everything. I tried all the home made contraptions that kill one at a time, but when there's alot-and 50 is about the norm, they would still multiply faster than I could kill them.
What works for me is this; rats are not a one time thing. Killing rats is a maintenance and you will always be doing it.
I cover all the feed at night. 5pm or so is great if you can do it. You need a spill proof way of feeding the chickens or clean up all the feed. Then buy those bait stations. The bait is round and has a hole in it so when you load it, it stays where it is. I have 4 (yes overkill) and you need to check on them weekly to see if the bait is eaten. When you find no new bite marks on the bait, your maintenance is good. But it does not end.
What works for me is this; rats are not a one time thing. Killing rats is a maintenance and you will always be doing it.
I cover all the feed at night. 5pm or so is great if you can do it. You need a spill proof way of feeding the chickens or clean up all the feed. Then buy those bait stations. The bait is round and has a hole in it so when you load it, it stays where it is. I have 4 (yes overkill) and you need to check on them weekly to see if the bait is eaten. When you find no new bite marks on the bait, your maintenance is good. But it does not end.