No, Catchmaster 612 Multi-Catch Mouse Traps will not work for small rats. We recommend that you use the Protecta Sidekick bait station with a Trapper T-Rex snap trap inside. This will protect your chickens from the traps and will prevent you from having to use any type of bait. The T-Rex snap trap is very versatile as it can be used inside of the bait station and it can be zip tied or wired to pipes or beams if you suspect the rats are running around on them.
If a larger mouse or multiple were some how able to push open the lid of the Catchmaster 612 Multi-Catch Mouse Trap, the easiest way to stop that from happening is with a couple of rubberbands around the unit. We have had a few customers put a book or something similar in weight on top of the unit if they did not have rubberbands. It's rare that this happens, but it is not something that renders the trap unusable or ineffective. As far as baiting goes, you should not be putting the bait in a spot close enough to the levers for that to interfere with anything or any moving parts. The bait should be far enough back in the unit that the rodents have to fully come inside the trap to get access to it, but not so close that they can just lean on the lever and feed and drag bait onto the lever. Overall this is a great trap for catching multiple rodents at a time without having to worry with resetting a snap trap daily. You can also use a glue board inside this trap, such as the Trapper LTD.
We would not recommend putting rodenticide bait in the Catchmaster 612 Multi-Catch Mouse Trap. Rodent bait can take up to five days to kill the mouse once they consume the bait. These traps are made to use with glue boards for faster kill. Using a glue board will also insure they cannot escape when you open the lid.
Mice should not be able to chew or push through the clear window of the Catchmaster 612 Multi-Catch Mouse Trap. The plastic sits on top so there are no edges for them to grab onto from inside the trap.
Yes, the top of the Catchmaster 612 Multi-Catch Mouse Trap opens for you to release the caught mice.