Utricularia vulgaris in Hodonínská Dúbrava forest

The critically endangered species Utricularia vulgaris has been re-discovered in Hodonínská Dúbrava forest after more than 20 years. Young plants were observed at one of the waterlogged terrain depressions (MS15) in spring 2014, but they did not survive to flower. Macrofossil analysis demonstrated the presence of viable seeds of U. vulgaris in the sediments of three wet depressions (MS3, MS4, MS15). The age of the sediment with viable seeds was up to 100 years, which suggests that the seed bank of the species is highly persistent. The presence of seeds in the youngest samples at localities without recent presence of this plant suggests that the species might occasionally have appeared and flowered also within the past 20 years. The most probable reason of the decline of U. vulgaris in Hodonínská Dúbrava is a lowering of the water table. Appropriate restoration management should be considered.