Pengudang villagers during Training of trainer (ToT) activity, learning how to conduct coral transplantation, Pengudang Mangrove School, Pengudang, Teluk Sebong, Bintan, Indonesia, 15 February 2025. Courtesy of Henky Irawan.
Pak Henky Irawan is a lecturer in the Study Program of Aquaculture at the Faculty of Marine Science and Fisheries, Raja Ali Haji Maritime University (UMRAH) in Tanjungpinang. His work focuses on coral restoration, but not only as a scientific practice, also as something that can be learned, shared, and carried out by local communities.
Pak Henky and other researchers at UMRAH have developed a method of coral transplantation that is simple, practical, and designed to involve local people. Through a Training of Trainers (ToT) programme in Pengudang village (northeast Bintan), villagers are taught how to carry out coral restoration themselves using small, easy to carry ‘paving blocks’. This method is developed with the idea that these activities can also become part of future eco-tourism initiatives.
In the video, Pak Henky explains how this method works.
Pak Henky Irawan explaining coral transplantation methods.
Demonstration of how mangroves can act as natural coastal
Using hexagonal paving blocks as a base, villagers attach small 5-centimeter coral fragments onto the surface. These fragments are usually taken from species such as Acropora, which grow relatively quickly and are commonly found in the area. Once prepared, the paving blocks are transported by boat and handed to divers, who place them carefully on the seabed.
The method is designed to be accessible. The paving blocks are easy to handle and can be prepared on land, allowing people of different ages and backgrounds to participate. Pak Henky also highlights the importance of involving younger generations, especially Gen Z, as they will play a key role in the future of coastal conservation.
Monitoring the corals is an essential part of the process. Growth is observed over time by looking at changes in size and colour. Healthy corals maintain their colour and gradually increase in size, offering visible signs that the restoration is working.
In areas with stronger currents and waves, Pak Henky and his team are experimenting with larger structures: one-metre blocks that are heavier, and thus more stable on the seabed. He compares them to large Lego pieces, designed to withstand movement while still supporting coral growth.
Through such community-friendly methods, coral restoration becomes more than a technical intervention. It becomes a shared activity that connects scientific knowledge with local practice, and opens up new possibilities for community-based conservation.
Tools and materials used for coral transplantation, including coral fragments prepared for attachment, during Training of trainer (ToT) activity, Pengudang Mangrove School, Pengudang, Teluk Sebong, Bintan, Indonesia, 15 February 2025. Courtesy of Henky Irawan.
A stack of hexagonal paving blocks, used as a base for attaching coral fragments before transplantation, used during Training of trainer (ToT) activity, Pengudang Mangrove School, Pengudang, Teluk Sebong, Bintan, Indonesia, 15 February 2025. Courtesy of Henky Irawan
Pak Henky Irawan and Pak Iwan Winarto explaining the use of tools and materials during a Training of Trainers (ToT) activity at Pengudang Mangrove School, Pengudang, Teluk Sebong, Bintan, Indonesia, 15 February 2025. Courtesy of Henky Irawan.
Village participants attaching coral fragments to paving block substrates as part of the restoration process, during a Training of Trainers (ToT) activity at Pengudang Mangrove School, Teluk Sebong, Bintan, Indonesia, 15 February 2025. Courtesy of Henky Irawan.
Village lady using a mini circular saw to cut a short fragment from a live coral, during a Training of Trainers (ToT) activity at Pengudang Mangrove School, Teluk Sebong, Bintan, Indonesia, 15 February 2025. Courtesy of Henky Irawan.
Villager indicating the center of the paving block where a nail will need to be attached, during a Training of Trainers (ToT) activity at Pengudang Mangrove School, Teluk Sebong, Bintan, Indonesia, 15 February 2025. Courtesy of Henky Irawan.
Contributor
Henky Irawan Marine scientist and lecturer in the Study Program of Aquaculture at the Faculty of Marine Science and Fisheries, Raja Ali Haji Maritime University (UMRAH) in Tanjungpinang
Henky Irawan is a marine scientist and lecturer at Raja Ali Haji Maritime University (UMRAH), Indonesia, with over a decade of experience in aquaculture innovation and coastal ecosystem management. His work focuses on advancing restorative aquaculture, integrating ecological restoration with sustainable production systems. He has led research on mangroves, seagrass, coral reefs, and commercially important species such as grouper and seaweed, producing impactful innovations including hydroponic mangrove propagation and engineered reef structures. Henky’s research aligns aquaculture practices with blue carbon strategies, biodiversity conservation, and community-based coastal resilience. He actively promotes ecosystem-based approaches that enhance habitat recovery while supporting livelihoods, particularly in Indonesia’s archipelagic regions. With a strong academic and leadership background, he contributes to bridging science, policy, and community implementation.
