Data presented here were collected between November 2013 to October 2015 within the BEFmate project (Biodiversity - Ecosystem Functioning across marine and terrestrial ecosystems; https://www.icbm.de/verbundprojekte/befmate/ ) of the Universities of Oldenburg and Göttingen and the Nationalparkverwaltung Niedersächsisches Wattenmeer. Experimental islands and saltmarsh control plots were created in the back barrier tidal flat and in the saltmarsh zone of Spiekeroog island. Data were measured with a local installed recording current meter next to the experimental islands in a tidal creek (0.71 m NHN). The current meter used here is a RCM 9 LW (S/N 32, Aanderaa, Bergen/Norway). The system was equipped with a current speed and direction sensor (RCM DCS 4220), a conductivity sensor (3919) a pressure sensor (4017), and a temperature sensor (3621). The sensor were pre-calibrated by the manufacturer. Recorded data were internal logged till readout with the Data Reading Program DRP 5059 software and processed using MATLAB (R2012b). Data were visually checked and outliers removed. Low tide data is removed. The position was derived from a portable DGPS-system. Date and Time is given in UTC.