05-29-2014, 10:34 AM
The car exhaust will work to a degree. I have used it as a humane put down of small animals - for that I just made a exhaust balloon of an old garbage bag and drop the creature in it, data within 5 seconds. The issue for your situation is the tunnels are very extensive and getting all the air pockets would be hard. Most likely at least one tunnel runs outside.
If it is an extensive population, as much as I hate to say it, poison is the best bet. You could try gas or traps first, but most likely it will be poison at the end.
If it is an extensive population, as much as I hate to say it, poison is the best bet. You could try gas or traps first, but most likely it will be poison at the end.