Enhancing biogenic shellfish reefs

Justé Motuzaitė
Stagiair ARK, studie Integrated Product Design

Justé Motuzaitė ontwierp voor de herintroductie van de inheemse Europese platte oesters structuren die de biogene rifvorming in de Noordzee kunnen versterken. Justé werd tijdens een internationaal uitwisselingsprogramma geïnspireerd door de manier waarop productdesign hier in Nederland werd onderwezen: niet om mooie consumentenproducten te maken, maar om als ontwerper een bijdrage te leveren aan een betere toekomst. Inmiddels werkt Justé bij ARK Rewilding Nederland om haar belangrijke werk voor het rewilden van de Noordzee verder voort te kunnen zetten. Lees hieronder het Engelstalige verslag van haar stage en onderzoek.

Rewilding and product design

"At first glance, product design and rewilding don’t have much in common: while one is mostly focused on improving the human lives, the other focuses on bringing ecosystem back to its resilient state. But both fields have a common approach: they search for ways to improve the future, explore possible solutions and actively develop them. My master study program of Integrated Product Design at TU Delft has taught me a lot about how the design approach, methods and tools can be used to develop future solutions and I believe they can also contribute to various rewilding projects and the creation of nature-centric designs.

Together with the partners, ARK is working on rewilding the North Sea. One of the interventions is reintroducing the native European flat oysters, which form biogenic shellfish reefs and help create important biodiversity hotspots where numerous species can live, feed and breed. With the supervision of Gwenaël Hanon, I joined ARK North Sea tea for my master graduation project to design structures which would enhance the biogenic reef formation in the North Sea.

Offshore windmill farms and ecosystem restoration

Design projects usually begin with understanding user perspectives, challenges, and needs. In my case, the main users were the marine ecosystem and European Flat oysters, which currently face numerous challenges: overfishing and habitat destruction have caused a sharp decline in marine species, including the European Flat oyster, turning most oyster reefs into underwater deserts. On the bright side, Europe's shift towards clean energy and more offshore windmill farms are being built in the North Sea. Within these highly protected zones, marine life could find a refuge from fishing and oysters could build the reefs there. But offshore context provides many feasibility challenges as well: oysters can become an easy prey for starfish and crabs, migrating sand waves can burry and suffocate them, young oysters often cannot find hard substrate to attach themselves to.  

To better understand the biogenic reef restoration context, I conducted multiple interviews with marine biology and ecology experts from ARK, conducted a literature review, and participated in two field trips involving young oyster deployment in the North Sea. Helping during young oyster deployment was very exciting, because I could experience the whole operation myself, hold the young oysters in my hands and learn from the marine experts while being there.

Éen maand oude oester

The design of oyster unit

During the design phase I have explored multiple solutions, from making structures with biodegradable ceramics to developing automatic self-expanding frames which would raise oysters from the seabed. I used various prototypes, from small clay or 3D printed models to full-scale structures, to discuss the ideas with the North Sea team, and test them out.

After multiple design cycles, the final solution was developed: two steel-frame gabions house young oysters, keep them in one place and protect from predators. The gabions are placed in a double-diamond shape between the two pallets with all assembly tightly secured with a cotton rope. The structure may look simple but, once deployed on the seafloor, can become home to numerous marine species: wood pallets get overgrown with barnacles, mussels, various types of sponges, sea anemones; Atlantic cod, crabs, lobsters, shrimp, and many species of juvenile fish can find gaps to hide from water currents or predators. These structures are designed to degrade and become a natural reef: the steel frame rusts away, oysters inside continue to grow and form the reef, and the wood pallets get fully overgrown with numerous benthic species.

Definitief prototype. Foto: Justė Motuzaitė


The marine ecosystem and Flat oysters do not speak the human language so I could not interview them directly. Nevertheless, working with ecology and biology experts at ARK has allowed me to better understand the North Sea ecosystem, Flat oysters, and their needs. In addition, engaging in-depth discussions and feedback on different design ideas has helped me in making important decisions that ultimately shaped the final design. In later product development stages, the marine ecosystem will be directly ‘interviewed’ by testing how it responds to the design, but it may take a long time before clear outcomes can be seen. Luckily, working in multidisciplinary team, with various skills, knowledge and perspectives on the table, can help navigate the complexity and ambiguity, facilitating the design of effective solutions for ecosystem restoration.

Sketch Biodiversity design project rewilding the Northsea

What’s next?

After my graduation, I was happy to join ARK and the North Sea team and work on this project further. Our next step is to put these oyster units for a test in the marine ecosystem: we will deploy 5 m3 of young oysters inside these 42 units in Voordelta in May. Updates on this operation will follow!"