Bonamia-free oysters: temperature and bacterial growth

To strengthen the natural biodiversity of the North Sea, several pilot projects are being carried out in the Netherlands to restore flat oyster beds (Ostrea edulis). Oyster cultivation is being investigated as a method to obtain sufficient source material. This project investigates the influence of water quality on the survival of oyster larvae.

Rearing the larvae to spawn has not been very successful so far. Due to the hot summer of 2018, there was a lot of mortality in the larval stage, both at the hatchery of the Roem van Yerseke and in the climate chamber of Wageningen Marine Research.

Analysing and comparing water quality

An analysis of the water quality is needed to gain a better understanding of the cause of mortality. Stichting Zeeschelp (ZS) is also interested in cooperation. They have helped NIOZ set up a hatchery on Texel and are now planning to produce flat oysters themselves in their hatchery in Jakobahaven. A comparison of the water quality of the hatchery at ZS (in the Oosterschelde estuary) and the hatchery of RvY (in the Oosterschelde Kom) may provide more insight into causes of mortality and success factors.