A data storage medium such as an optical disc with separate image and data tracks, and a method and apparatus for forming the same. The medium has a user data storage area with a data track to store user data, and a non-user data image track to store human readable information to form a watermark interspersed with the user data. Preferably, the data track forms a portion of a first spiral and the image track forms a portion of a distinct second spiral nested within the first spiral. Alternatively, the data and image tracks are nested concentric circles. An increased track pitch is preferably provided for the data tracks in the data storage area adjacent the watermark to accommodate the intervening image tracks, and a reduced track pitch between data tracks is provided elsewhere. The medium can be pre-recorded or recordable.