Fish Hives into the Caribbean sea
Kathryn Whittey
Cardiff University

Corals create complex, 3-dimensional structures which then provide a plethora of habitat space for marine life. Coral reefs are some of the most diverse ecosystems in the world and despite only covering 1% of the ocean they support up to 25% of life in the sea. But, unfortunately due to climate change and a number of other anthropogenic stressors coral reefs are declining. This is not only impacting the marine life that directly depends on the corals for habitat, but it also affects communities who depend on the reefs for livelihood.
During my time in Tobago, it was clear that many fishers and members of the community, aware of their declining reefs, were keen to do something to help but struggle to see what their options are. I’d seen artificial reefs been used as one technique to restoring coral reef habitat. These structures, often made from concrete, provide an alternative habitat space that was once provided by coral. Additionally, as concrete is porous, over time natural benthic settlement of organisms. At home in Wales, I started to ask around about concrete, and together with my family, in our garden, we designed a concrete structure which mimics some elements of the corals I’d seen on the reef. We made 1-metre-high concrete domes with a hollow inside. We knew we wanted the hollow inside to provide refuge for fish, and it was important that the whole process could be repeated on the small island of Tobago using minimal resources. We landed on an inflatable mould, a space hopper! These could be take out with us in our suitcases. Then, we layer concrete around the spacehopper, placing in small pieces of wide bamboo to create holes that would lead to the inside cavity. The resulting structure we named a Fish Hive!

In 2019 we successfully deployed 12 Fish Hives into the Caribbean sea in Tobago. The structures were seeded with corals and the spacehoppers, having survived several rounds of building, went to the local children in the village. Because of the COVID-19 pandemic we were unable to return to Tobago to see the structures in person, but I completed the chapter for my PhD using footage collected by our collaborators Environmental Research Institute Charlotteville ERIC.
While the installation of artificial reef structures is a positive step toward reef rehabilitation, effective monitoring is crucial to assess their success and ensure their long-term sustainability. By continuing to monitor these structures we are gathering valuable data to allows scientists, conservationists, and local authorities to assess the impact of these artificial reefs.

In June 2022 with the help of the Challenger Society Stepping Stone bursary I undertook research trip to Tobago to return to sea the hives for the first time since deploying them in 2019. After 3 years away from the reef I was anxious about what I might find. The Caribbean had had several warming events since I’d last been out, and I hadn’t seen any footage of the hives for about a year. But, when I arrived I was greeted by numerous old friends both on and off the reef.
I’d flown out to Tobago to take part in teaching the Cardiff University marine field course for undergraduates. I was thrilled to receive the bursary, the funding covered the costs of extending my stay in Tobago to undertake additional field work on the hives, as well as transport across the island to meet collaborators and discuss future planning for the project.
I removed tangled fishing line, re-seeded corals that hadn’t made it and collected additional footage for long-term monitoring. I was able to monitor the colonization and utilization of the structures by different marine species. This helps identify trends in species richness, abundance, and diversity, offering a snapshot of the reef's ecological health. Using photographic data, we can track the growth of coral, sponges, and other sessile organisms on the structures. We also take video footage of our structures which allows us to assess the behavioural interactions of marine species with our structures.
The funding also allowed me to network with local fishers and scientists to discuss the future potential of the project. Community involvement in the project is key and we have engaged relevant peoples (‘stakeholders’) in the community to be involved in the project. Through our research and conservation efforts, we aim to leave a lasting positive impact on Tobago's marine environment. By combining scientific expertise, community engagement, and innovative restoration techniques, we hope to set a precedent for other regions grappling with coral reef degradation. Together, we can safeguard these precious underwater ecosystems and ensure a vibrant future for Tobago's coastal biodiversity.
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Townhall on UK Arctic Ocean contribution to International Polar Year 32/33
The Arctic is one of the most rapidly-changing regions on our planet, with impacts on global sea-level rise, changes to our climate and weather patterns, and threats to our shared biodiversity and ecosystem services. With the international community rapidly mobilising towards the International Polar Year 32/33, and with new international programmes and initiatives now being shaped, it is timely for the UK Ocean Science community to come together and articulate what its unique offerings could be to Arctic research and technology.
This hybrid 2-day meeting, to be held at NOC Southampton, is intended to start this process. Recognising the Arctic Oceans role in global Earth and Human systems, anticipated outcomes include a high-level shaping of what the UK Arctic Ocean community would like to achieve over the course of the IPY, stimulation of new collaborations and proposals for grand Arctic challenges and a baseline from which wider integration with terrestrial, atmospheric and cryosphere communities, both in the UK and overseas, can be built. Discussions will continue in diverse forums, including the UK Arctic Science Meeting in September and at Challenger 2026.
This action is supported by the UK Arctic Office and UK Arctic and Antarctic Partnership
Further details and meeting registration link will be circulated in April together with a questionnaire to help shape the agenda and discussion
In the meantime…SAVE THE DATE
Potential Availability of NERC Ship Time During the 25/26 Programme Year
The NERC Marine Facilities Programme for 2025/2026 for the RRS Discovery and the RRS James Cook has been published on the Marine Facilities Planning website.
The RRS Discovery programme currently contains a 79 day alongside slot between the 2nd of November 2025 and the 19th of January 2026, which is available for science delivery if funded science projects can make use of this time. Due to the location of the vessel, the ship is most likely to be able to deliver fieldwork in the North and East Atlantic regions. Some support for science capability within the National Marine Equipment Pool is potentially available, although there is no capacity for use of autonomous vehicles or remotely operated vehicles. Any fieldwork within Exclusive Economic Zones (EEZs) will need the appropriate diplomatic clearance submitted to coastal states at least 6 months in advance, and to NMF with sufficient lead time for processing via the FCDO.
If interested in making use of this ship time, please contact NERC Marine Planning (marineplanning@nerc.ukri.org) ASAP to start discussions.
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