There's a rat-catcher on here, from Manchester way. I can't remember his username though (might be 'the ratchatcher')! He'd know what to do
Yes, it is The Ratcatcher. If you've got two rats now, by the spring you'll have at least twenty, probably more. Rather than use rat poison, the best solution is properly sited traps, especailly BMI Magnum 110's, which I use a lot. These traps are 'pass-through' type traps, which increases the catch rate and the kill probablity, and they don't need to be baited if you know where the holes are.
If you want any info PM me, and I'll give you all the info you need.
Alan