Flying Snails—how Far Can Truncatellina (Pulmonata: Vertiginidae) Be Blown Over the Sea?

With populations of land snails of very small size like Vertiginidae, questions have arisen as to whether populations of relatively distant islands in archipelagos are really isolated from each other. Apart from other flight agencies, airborne transport of loose specimens is not improbable in stormy weather conditions. Currently, mechanisms of wind-borne transport of sand particles over short and long distances have been intensively studied. The results are available in the literature on sediments, allowing the calculation of probable flight distances for particles in suspension. For living snails of the Aegean species Truncatel-lina rothi, an average fall velocity of 2.6–2.7 m s−1 has been determined in experiments under laboratory conditions. Applying these results, Truncatellina living on an island at 100 m altitude and close to the coast could be transported up to several kilometers in heavy storms, which are not uncommon in the Aegean archipelago (Greece). This would imply that many of the Aegean islands are not effectively isolated for minute snail species, and that genetic interchange between island populations is probably frequent.