I'm afraid I don't have a photo but can anyone confirm the likely identity
of the layer of these droppings.

They're jet black, about 4" long and around as thick as my little-finger
(1.5cm), straight and tapering to a point at one end.
Not obvious remains of seeds or insects in them that I could make out. They
only seem to appear overnight.

I'm assuming it's a hedgehog, am I right?

(Apologies for the mixed units)

Tim.