Coral reefs are vital ecosystems that support immense biodiversity and provide essential services such as coastal protection, fisheries productivity and livelihoods for millions of people. Despite covering just 0.2% of the seafloor, they sustain around a quarter of all marine species. However, reefs are under severe threat from climate change, ocean acidification, pollution, and unsustainable fishing practices, leading to widespread habitat degradation. Long-term monitoring has been central to understanding how reefs respond to these stressors, and in Indonesia’s Wakatobi region, over 25 years of research at Hoga Island has provided valuable insights into coral cover, fish communities and reef structure.
In recent years, reef restoration efforts have been trialled as a way to support recovery. At Hoga, the MARRS (Mars Assisted Reef Restoration System) protocol was introduced in 2019, using metal “reef stars” to stabilise rubble and promote coral growth. Ongoing monitoring has revealed differences in coral survival across depths, positions on reef stars, and interactions with competitors such as sponges and algae. Recent surveys, including photographic monitoring and 3D mapping, have generated rich datasets to evaluate restoration success and inform future strategies. These initiatives not only provide opportunities for adaptive management of restoration projects but also allow participants to engage directly in data collection and maintenance. Potential student research could focus on comparing coral survival across depths, assessing the impact of sponge overgrowth, or evaluating the structural complexity and habitat function of reef star installations.
If you would like to do a dissertation or thesis with us but your university hasn’t started dissertation planning or the project selection process, that’s no problem. You can cancel your expedition with zero cancellation charges up until the 15th of April of if you provide documentation from your university saying that they won’t support completing a dissertation project with us.
The Coral Triangle is a marine region that spans Indonesia, Malaysia, Papua New Guinea, the Philippines, the Solomon Islands and Timor-Leste. This region is recognised for having the highest diversity of marine species anywhere on the planet. At the very heart of the coral triangle, at the epicentre of biodiversity, lies the Wakatobi Marine National Park, the location of Opwall’s marine research base in Indonesia. The Hoga Island Marine Station has been the centre for Opwall’s Indonesian marine research programme for nearly 30 years. During this time, teams of international and Indonesian scientists have worked at this site during the Opwall survey seasons and as a result have produced more than 200 peer-reviewed papers. The research outcomes and discoveries from these studies have had local, national and international significance.
For the last 15 years, Opwall has also been running an extensive monitoring programme around Hoga and eastern Kaledupa for macroinvertebrates, fish communities, coral cover and community structure. In 2026 the long-term monitoring programme will continue, however there will a new research focus introduced. Like many coral reefs globally, the Wakatobi has experienced recent changes in benthic community structure and a reduction in the size and abundance of many reef fish species. Our ultimate goal is to develop an ecosystem model to represent the current dynamics of the marine ecosystems in the Wakatobi to help support future management decisions. To support this goal, work in the regions will focus on understanding the consequences of these changes in benthic community structure to the productivity of coral reefs in the Wakatobi and the resources these reefs provide to local communities. In 2026 research projects will focus on describing the extent of shifts from coral dominated states to reefs dominated by other groups including sponges, ascidians and soft corals, and the potential of deep reefs to provide refugia for sharks, rays and other predatory fish.
Building on nearly three decades of research at the heart of the Coral Triangle, reef conservation efforts at Hoga Island now include active restoration work to support long-term reef resilience. Since 2019, the Mars Assisted Reef Restoration System (MARRS) has been implemented at selected sites, using steel “reef stars” to stabilise rubble and encourage coral growth. Ongoing monitoring has provided valuable insights into how restoration structures influence coral survival, habitat complexity, and overall reef health. In 2026, students will contribute to research examining how these restoration efforts can enhance biodiversity and ecosystem function, complementing the long-term ecological monitoring already in place. These conservation initiatives are vital to protecting the rich marine life of the Wakatobi and ensuring the continued ecological value of one of the most biodiverse marine regions on the planet.
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Climate
At the marine sites during the day, the weather is normally sunny and warm (around 30 degrees Celsius), and the night temperatures drop to around 20-25 degrees Celsius. Being on the coast means there is often a pleasant breeze so it does not always feel this hot. It rains rarely, but when it does it tends to be very heavy for short periods of time.
Fitness level required
Low-Moderate. Some fitness is required for in water activities, but conditions are relatively easy.
Creature comforts
The Hoga Island Marine Station is an established facility that lies within the Wakatobi Marine Park of eastern Indonesia. The station was rebuilt in 2016 and supports a dive centre, lecture theatre, wet-lab as well as a large dining room and kitchen facility. Simple huts owned by members of the local fishing community surround the station and serve as guest accommodation. The island supports reliable phone signal that allows limited internet access.
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More information on how the dissertation/thesis projects run within Opwall and what you will need to do
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