A new peanut worm for Belgian waters, and another European flat oyster

On 20 October 2022, a mooring block used for underwater noise monitoring that had been lying on the seabed for three years was recovered from the Seastar wind farm by scientific divers from the Royal Belgian Institute of Natural Sciences. This operation was carried out as part of the research carried out by the research vessel RV Belgica.

The anchor block had a structure that was supposed to serve as housing for a buoy cable but was now filled with sediment. In that sediment, researchers from the research team MARECO (Marine Ecology and Management) found nothing less than a new species for the Belgian waters, the peanut worm (Sipuncula) Nephasoma rimicola. The species is known from the northeastern Atlantic and has also been found in the English Channel, but was thus not previously observed in Belgium.

The peanut worm Nephasoma rimicola, new to Belgian waters (©RBINS/F. Kerckhof)

On top of that, a European flat oyster Ostrea edulis, estimated to be 2-3 years old, was found on the anchor block itself (bottom right of photo). Molecular techniques will be used to determine the origin of the oyster. A promising observation for possible oyster recovery projects in the Belgian part of the North Sea! (For background on the exceptional nature of this find, see here, among others).

The European flat oyster Ostrea edulis (bottom right) (©RBINS/J. Vanaverbeke)