Survey data were acquired for four sea caves within the Fair Isle MPA for the purposes of condition monitoring. The information included physical data on the location and spatial configuration of the caves enabling their mapping, as well as depth data and descriptions of the physical habitat. Biological data in the form of SACFOR abundances were collected for cross sections at various points along the cave system, permitting the identification of biotopes present. Imagery collected included still photo and video footage along the cave system, with detailed coverage of the substrate and biota of the biotopes present at the cross-sections. In addition a cave inventory of Fair Isle caves was produced based on historical information and examination of the coastline by boat, with cave entrances photographed and positions recorded. When sea conditions allowed caves were entered by snorkellers and data collected on cave configuration, extent, water depth and light levels, and wherever possible, a sketch was made of the cave layout.