NIOZ Western Wadden Sea subtidal macrozoobenthos survey

The first subtidal survey was conducted during a one-year period in 1981-1982. The survey covered the subtidal parts of the western Wadden Sea, i.e. west of the watershed between the island of Terschelling and the mainland, except for the Eierlandse Gat tidal basin. A total of 459 stations were sampled along 45 transects scattered over the entire area. Most transects were situated perpendicular to the direction of the tidal channels. Most attention (380 stations) was paid to the area between MLTL and MLTL – 4 m. 35 stations were located within mussel lots. Sampling was done with a 0.2 m2 van Veen grab and a 0.02 m2 flushing sampler modified for subtidal sampling from a large vessel. At most station, 3 samples with the flushing sampler and one Van Veen-grab sample were taken. In 2008, these transects were revisited in the framwork of the PRODUS project. Since 1989, three subtidal transects are sampled in late winter (February-March) and late summer (August-September) with a 0.06 m2 Reineck box-corer up to 45 cm in depth (min. 15 cm). At each transects of 1500 m 15 samples are collected. From each of these cores a subsample (core diameter 4.25 cm, depth 4 cm) is taken for Hydrobia ulvae.