Change index: a measure of change in range size that is independent of changes in survey effort A major problem in studying the range changes of invertebrates using atlas data, is discriminating the effects of changing survey effort from the real biological changes. Using the data sets collated by the UK Biological Records Centre, a method has been developed which allows for the effects of variation in survey effort, by calculating an index of relative change in range size. The method is applicable to a wide range of atlas data sets.

Additional Metadata
Keywords Change index, Decline, Distribution atlas, Recorder effort
Publisher European Invertebrate Survey - the Netherlands, Leiden
Editor M. Reemer , P.J. Helsdingen , R.M.J.C. Kleukers
Citation
Telfer, M. (2003). Change index: a measure of change in range size that is independent of changes in survey effort. In M Reemer, P.J Helsdingen, & R.M.J.C Kleukers (Eds.), Changes in ranges: invertebrates on the move. Proceedings of the 13th International Colloquium of the European Invertebrate Survey, Leiden, 2-5 September 2001 (pp. 107–110). European Invertebrate Survey - the Netherlands, Leiden.