In December 2015, an inventory was made in two salt marsh creeks east of the Kobbeduinen dune ridge at the island of Schiermonnikoog (province of Friesland). In the so-called ‘Derde Slenk’ one live adult Cerastoderma glaucum was found, belonging to year class 2012 or 2013. This is the first time a live specimen was found in this creek. In the ‘Vierde Slenk’ the species was not found.