Yesterday - a dead rat, in our garden tool store. I should check the trap in there more often. I realised it was there because of the smell. Had to leave the door propped open all day, & take out the deckchair, to air.
Well, at least the trap works. Next step is to close off the bottom of the compost bin. It's open to the ground, so worms can get in to finish off the compost, but now I have some 13mm galvanised wire mesh, which should keep rats out without obstructing worms.