As part of a scheme to monitor the distribution of otters throughout the UK, three Scotland otter survey have been carried out covering the years 1977-79, 1984-85 and 1991-94, funded by the Vincent Wildlife Trust (VWT). These surveys were conducted at the 10km square level. Coverage was most extensive in 1977-79 and 1991-94, nearly every 10km square in Scotland was visited. Within each 10km square, sites visited were selected by accessibility and likelihood of finding signs of otter activity—typically road bridges and the confluences of watercourses. The number of sites visited per square varied, averaged about 5. No attempt was made to randomise the sampling effort. The number of spraints was recorded. Mink are not recorded in this database.
There are also Otter Survey databases for England, Wales and Northern Ireland following the same protocol at differing resolutions.
