Just ‘cos we’re on pests - I’ve had rats recently and tried so many things but finally the cat got a couple and finally the traps I laid months ago started catching too. Most effective has been tomcat snap trap with fresh malt barley as a bait. So good, I even caught my own finger in it yesterday.
I suspect it may be a lazy rat that has been eating my tomatoes. Only the ones low down on the plant at about rat hight have been half eaten.
I have found the Nooski ring traps from Bunnings pretty good but only in warm weather though as the rings don’t close fast enough when they are cold. They are a safer option to snap traps if you have cats or other pets.
Rats are very wary of baited traps. Loughran Family Stout malt or Gladfield Ale works best as bait I have found. I have had very limited success with Joe White Trad.
The best way to catch rats is use unbaited traps like this
http://www.fenntraps.com/mk4-fenn-spring-trap.html in a tunnel. Rats don’t like being out in the open and love the cover a tunnel provides if you place it on their runs next to a wall or fence. Only thing is when I tried to buy one in NSW a few years ago I couldn’t find one and think they are illegal to use here so check the regulations in your state.
When I was a kid I had 100% success rate setting spring snares on rat runs but again I think they are illegal to use in NSW.
A good book on rat catching is
Tales of a Rat Hunting Man by D. Brian Plummer one of his methods is using a garden sprayer to vaporise and spray petrol into a rat warren and blow it up by throwing a match from a safe distance.
As a kid me and my mates had a similar method using rocket fireworks. Just break the stick off a good sized rocket, place it at the entrance of a burrow and light the fuse. It would go deep down the burrow and any rats not killed when it exploded came out disorientated and could be easily shot with an air rifle or hit with a stick.
Again, act responsibly though and check regs in your state before trying that. And obviously not if there is a fire ban in place.