| My house is in a subdivision in the foothills near Los Angeles. I am on a hill and directly behind my house is an open area with thick brush so I get various critters in my yard from time to time. I have installed 1/2" wire mesh to keep out the rabbits and snakes but some varmints get in anyway.
In the last 7 years I have caught about 4 field rats that have wondered in. Now in the last couple of years we have had many brush fires that seemed to have directed many of them into my yard. Having a garden doesn't help.
In the last two weeks I have caught 5 rats and one that kinda got away. I have been using the Victor plastic power traps. They are much more effective than the older wooden ones.
You can also release the catch without touching them. They are also easier to set. I drop a peanut into the center pocket. They are not 100% effetive but prerry close.
I had one trap in my greenhouse that was very bloody but no sign of a rat inside. I then picked up the trap and found the following. The poor guy must have been brave to chew off his paw to get away.
haha. I really just wanted to point out that these traps really work.
Chris | 
