Mollusc (non-marine) data for Great Britain and Ireland

Quality Control

In the phase leading to the publication of the 1999 Atlas, initial validation of the records was carried out by automatically checking that the grid reference occurred within the recorded Vice County stated. The distribution maps of the data were visually checked by Michael Kerney prior to publication of the Atlas. Subsequent Honorary Recorders have sought to maintain an equivalent standard of data quality.

Method steps

1. The records in this dataset are the results of the Society's non-marine census which has been run since 1876. The dataset includes all accepted digital records held by the Society up to the time of publication. The dataset includes data from the cards that were originally digitised at 10km square as part of the publication of the 1999 non-marine mollusc Atlas; a redigitisation of those records at finer scales; and a substantial and growing number of subsequent records.

The dataset covers both Britain and Ireland though the data available for Ireland is not definitive. Note that some effort was made ahead of the publication of the 1999 Atlas to sample areas which had been under-recorded. The Conchological Society does include the Channel Islands, but these records are not included in the database.