Fish hives: artificial reef structures restoring coral colonies

Coral reefs are tropical habitats made from living coral that thrive in the warm waters of the world. Unfortunately, due to global warming, these delicate corals are being damaged and the habitat they create is turning to rubble. In response to this, many research projects have been initiated focusing on restoring corals and rebuilding reefs. Newly graduated KESS 2 alumna, Dr Kathryn Whittey, is one such researcher. In 2019, Kathryn led a team in the design and deployment of artificial reef structures thus attempting to restore this essential habitat into the marine environment.

During the project Kathryn and her team created the artificial reef structures, known as fish hives, by layering concrete around a Space Hopper children’s toy. The large round toy provided the ideal cost-effective mould shape for constructing the fish hives. The hives were then deployed in the ocean, in this case off the coast of Tobago, in the attempt to create a solid foundation for coral reefs to re-establish themselves.

Three years later, Kathryn returned to visit the fish hives and saw that the corals had grown very successfully with many fish and reef creatures settling on the hives and using the structures as their home. In a recent interview with Aled Hughes on Radio Cymru, Kathryn spoke about returning to the reef to see the hives in action.

Kathryn said,

“It was great to see how much the corals on the hives have grown. They have formed layers between the hives and there are creatures living in-between those layers as well. I wanted to be able to see inside the hive structures and I was very pleased to observe pink algae growing there, which is something we were not able to see from photos or videos. The algae is very important to the reef because it creates chemical messengers which attracts coral. This is excellent progress as we know the coral is going to be able to settle on the hives due to the pink algae already being there.”

Through Kathryn’s work on coral reef fish interactions, she hopes to uncover the importance of habitat and pinpoint which particular structures fish need to carry out their natural behaviour. The relationship between habitat and fish behaviour is particularly relevant to fish welfare and could have important applications in Welsh fisheries, enhancing future aquaculture initiatives.


Listen again to Kathryn’s interview on BBC Radio Cymru (item begins at 39:00)

You can follow Kathryn’s progress on social media at: