Sunday 02 April 2023

Dutch zoo works with Delft start-up to restore coral reefs

Lowering a block into position. Photo: Burgers Zoo

Delft based start-up Reefy has joined forces with Burger’s Zoo in Arnhem to develop sustainable methods for restoring coral reefs in the wild without using steel, concrete and plastic.

Biologists from the zoo worked with Reefy and the University of Wageningen to test whether or not corals could grow on biodegradable materials, using the coral in the zoo’s 750,000 litre aquarium.

‘We have developed the first, stable, artificial reef to boost biodiversity,’ Reefy co-founder Leon Haynes told Dutch News. The artificial reefs are composed of blocks made from heavy biopolymers and are 100% biodegradable.

‘The coral needs a base to grow on. By the the time the coral is mature, the materials will have fully degraded,’ says Haynes.

The blocks were first tested in wave tanks in Delft to check their ability to withstand hurricanes. They also have an inbuilt tunnel system so that fish and other sea life can shelter inside it.

Coral is vital for the biodiversity of the ocean as crabs, lobster, and many other animals live and breed in the complex habitat it creates. They also provide essential barriers against storms which lead to island erosion.


Zoo biologist Max Janse, told Dutch News the sustainability of the material was integral to the project. ‘We could only move forward with this project if we had the exact data on the materials and if they underwent toxicity tests.’

‘Toxic materials, sewage, and dynamite fishing stresses the coral reefs, causing them to reject the algae growing on them and become bleached. The algae creates sugars which provide 80% of the coral’s food source. Without this food source the corals will die within two to three weeks.’

Reefy is currently sourcing funding to begin the process of putting the blocks into the wild within the next year.

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