Using the Jolly-Seber model to characterise Xerolenta obvia (Gastropoda: Geomitridae) population

The terrestrial snail species Xerolenta obvia (Menke) has colonized dry, steppe-like habitats that have been created as a result of human activities in many countries outside the natural range of this species. In Latvia, this species was first recorded in 1989 in Liepāja. Observations in recent years in Liepāja have shown that snails from their initial introduction sites on the railway have also spread to the sand dune habitats within the city limits. Given that there are no snails in dune habitats that are biologically equivalent to X. obvia, this species is considered to be potentially invasive. As the distribution trends of this species in Liepāja indicate a possible threat to dry habitats in natural areas, detailed study of the species was conducted for the population of this species located in Dobele. Monitoring was performed from May 26 to August 5, 2019, carrying out 11 surveys with one week interval using the capture and re-capture method. The maximum recorded distance travelled by of one snail was 29.7 m; the calculated minimum estimated population density was 170 individuals and the maximum was 2004 individuals.