So I've got rats under two of my poultry sheds. The cat brought in one the other day that was 18 inches long (12 inches of body, 6 inches of tail). Anyhow, not sure whether this applies to all councils but our local one sends out the pest controller for free for all rat problems. He came today and reckoned they're getting in and out of the poultry run over the seven foot fence. They're definitely getting in and out because there's not enough water in the run for them to be breeding there. Given the run is currently half mud bath with plenty of water around for the ducks, this was quite surprising. He's set poisoned bait points on the outside of the run because even a grain of the bait is fatal to the chickens and will come back and check it weekly until we're clear. Yay! He did say the freebie service in theory only applies within a certain (short) distance of the house but for the sake of simplicity they don't normally charge at all (given he was about 200m from the house at the time, I was pretty happy!). Worth a try elsewhere?