Mapping of the entire intertidal area of the Isle of Man, estimated at circa 150 km, was carried out between Autumn 1999 and Autumn 2002, using Phase 1 and Phase 2 survey methods developed by JNCC. In order to assist Phase 1 field mapping a complete set of aerial photographs were taken at a scale of 1:7,500, digitised, and orthorectified.

A total of 82 Phase 1 surveys were carried out and all results placed onto a GIS package. During these surveys 66 biotopes were identified, over a total intertidal area of 16 million m2.A limited number of Phase 2 surveys were also carried out in order to study areas of interest, typically either for being representative or particularly unusual, in greater detail. A total of 22 sites were surveyed during 1999 and 2000, and the data added to a database developed by CCW.