A marine biologist collects coral spawn at the shoreline using a plastic cup, entering the water at depths of up to 0.5 m to avoid collecting coral spawn that’s been washed over the sand, as this could affect its viability.
Collected coral spawn is then incubated in rearing containers in an onshore laboratory. On day five of incubation, we check how many eggs have created viable coral larvae.
At the wind turbine foundation, the coral larvae are released into custom-made seawater enclosures that are attached to the foundation with magnets. Neoprene sealing lines the enclosure, and a mesh cover allows the enclosures to be replenished with the surrounding seawater.
The larvae are left in the enclosures for four days, giving them time to attach themselves to the foundation. After this, we remove the mesh cage structures, exposing the coral to the surrounding water column and allowing them to grow.
For the seeding of coral larvae in the proof-of-concept trial, 1 m2 areas on four separate foundations will be used. The areas will be positioned 1 m below the lowest tide level. This will ensure that the corals are submerged by water, receive an adequate amount of light, and are accessible for deployment and monitoring purposes.