Make sure you are wearing gloves when handling traps, bait, etc. The rats can smell a rat! They are pretty smart.
You might also like to try the mouse and rat attractant that is sold. It is a paste that comes in a tube and the makers claim it is more effective than cheese. It looks a little like peanut butter, which I have also used successfully in the past for catching mice. - greygardener
I am deployingthese bait stations. Rodents are rife around here at the moment, killing plants and getting in the house.
If they're near your house use traps not baits. With baits they go back to their nest and die, if that's near where you spend time you will have a very unpleasant smell while it decomposes, if you trap them then you can make sure they are disposed of properly. I have had a lot of success with peanut butter on standard spring loaded rat traps. - royq
I have found that the nooski rat traps from bunnings seem to work much better than conventional traps. Their design also reduces chances of catching birds, etc. I have always had success with peanut butter but the abundance of other options may reduce effectiveness, so think about placement. -JDE
I recently found an excellent repeller for mice which is all natural and may also work on rats. I also used to have scratchings every night in my walls and they were too loud to be mice so most likely bush rats, which are in my area. Not a sound since so I'm guessing the repeller has worked on them as well!
It simply consists of cotton wool balls soaked in Peppermint oil and strung onto a piece of wire so they are all together. I placed them in front of the doggie door, where the mice were getting in. For a garden area (providing it wasn't too large) you could soak some sticks or some lengths of thin dowel in the oil and lay them along the garden perimeter. - Prof
Yates has this humane solution that only needs batteries: theRatsak Electronic Mouse Trapis a highly effective way to control mice, using advanced smart circuit technology that senses when a mouse has entered the trap, while a uniquely designed tunnel prevents escape. Once inside, the circuit triggers a high-voltage shock, killing the mouse quickly and effectively. The electronic trap kills up to 100 mice (per set of AA batteries) and can be baited with peanut butter. - Wy