hmmm
Identifying woodworm is easy as tiny holes, know as flight ‘holes are left all over the timber, saw dust may also be present below the timber. The ‘holes are left behind when the larvae of the beetle exits the timber, these ‘holes are normally 1.5 – 2.0 mm in diameter. There are more than one species of beetle which cause woodworm one of which is called the deathwatch beetle.
Well i think it might be deathwatch, but I am no expert and Kenty and Susie might be right and its slugs, snails or rats!
*lays salt and gets in Rentakil then stands on the nearest chair*