Spatial analysis of genetic variation as a rapid assessment tool in the conservation management of narrow-range endemics

Abstract

The number of narrow-range taxa of conservation concern is steadily increasing. As a consequence, there is an urgent need to obtain data on their spatial distributions and to determine how genetic diversity and population structure are affected by fragmentation. This paper outlines the way in which spatial analysis of genetic variation can be used to guide conservation management decisions using allozyme data for the endangered endemic terrestrial mollusc Meridolum corneovirens (Pfeiffer, 1851) (Pulmonata : Camaenidae). Spatial autocorrelation analysis indicates that M. corneovirens populations are highly structured at very short distances (2 m) and that the radius of a genetic neighbourhood is approximately 350 m. An estimate of genetic neighbourhood size is a particularly useful parameter to have available for a species, especially from a conservation management perspective. It gives an indication of the distances moved by individuals between birth and breeding and hence the size of gaps in distribution that can be filled within a generation. Furthermore, replicate samples need to be separated by more than 350 m to be considered independent. Allozymes and spatial autocorrelation analysis can be used to obtain relevant management information for some species of conservation concern in a rapid, cost effective way.