Having lived on board for 14 years, we have always been careful with vermin coming on board. We have only tied up once in the last two months which was over 2 weeks ago.
two days ago Sue saw a rat under the spray hood, it scarpered pretty quick, and we did find evidence on deck of droppings, but so far nothing down below.
I high tailing it in the dinghy two miles to the local town to get traps and poison. I discovered that although I could get a trap, Poison was not easily available any more. I would have to go to a specialist pest control place.
Now it seems that Rat Poison has been missed off as an important item on a Cruising boat.
So I suggest that before leaving port, you obtain some and keep carefully stored in the boat supplies.
I know there may be many legal angles to stop you doing so, I just thought anyone setting left should consider it and not be caught out like us.

We have not seen or heard anything since the original sighting, or little clues left on deck. but we are extremely vigilant now.

This has been our finding in Greece, and assume the same would apply to most EU countries and possibly most first world countries.

Brian and Sue
S/V Darramy in the Peloponnisos