Royal Netherlands Institute for Sea Research

Brackish Pearl

VBK-Pilot Study Shelllfish Aquaculture

Brackish Pearl 'Brakke Parel' is an experimental study looking at the growth potential of cockles in an intermediate area between two dykes, a so-called 'double dyke' area. The underlying objective is to explore the possibilities of cockle mariculture and investigate optimal conditions for profitable cultivation on saline agricultural land.

A one- and two-year-old cockle. Photo: Kiki Dethmers

Polder Wassenaar

The experiments are carried out in Polder Wassenaar (PW) on the island of Texel. PW is a two-hectares piece of land made available by Staatsbosbeheer, with the condition that the entire area (17 hectares) will be released upon completion of the experiments and developed into a brackish nature reserve with high water refuge and breeding areas for birds.

Previous studies

A series of raceways (flumes), connected to the Wadden Sea via an underground pipeline, form the hydrodynamic field-laboratory of Polder Wassenaar. Our previous studies found that cockle brood, collected in the Wadden Sea and released Polder Wassenaar, grew rapidly and apparently much faster than usually observed in nature. Polder Wassenaar appears to provide advantageous conditions for cockle growth.

In the current experiment, young cockles (spatfall from 2018) have been released in a series of enclosures placed within the raceways and their growth is monitored under varying water volumes of Wadden Sea water and associated nutrient supply.

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  • Promising results after successful first season with cockle cultivation on soil land. Interview by Anja  Roubos in Noord Hollands Dagblad with Katja Philippart. Interview


Supervisor Katja Philippart

Project leader Kiki Dethmers (for contact)

Project information
Linked department:
1 Jan 2015 - 31 Dec 2019
  • Meromar Seafoods B.V.
  • Zilt Proefbedrijf

Meet the team

Philippart, Katja
Research Leader