leeneia - "No doubt to our US friends, a rat is pretty mundane fare"
I wasn't suggesting that in the US you have rats all over the place. I meant that a rat would be pretty mundane fare compared to the skunks, porcupines, raccoons etc. that appear from time to time on threads from our US friends. Sheesh! Seems like however carefully you phrase a comment, someone somewhere is gonna take offence....

Anyway, thanks everyone for the useful suggestions. I don't think I'll be going down the route of shooting the rat though - I'd have to sit out there for hours waiting for it to put in an appearance - and then would probably only wing it. Poison seems a bit extreme as well as I do harbour a bit of a soft spot for little beasties and couldn't contemplate it slowly bleeding to death. Best idea seems to be a quick, clean death via a rat-trap. As it happens, I haven't spotted the rat for a few days now, so possibly it's moved on and saved me the trouble!

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