Does a pilot need to be issued with a visitor identity document by the ship?

No.

MSC/Circ. 1156 advises: “The issue of visitor identification documents by the ship to public authorities, emergency response services and pilots who have provided, when seeking to board the ship, verifiable identity may not be warranted and may exhibit, in lieu of visitor identification documents issued by the ship, their official identification documents.” (Para. 4. 6)