Picturing Bangka’s Reef Biodiversity

Among the scientists exploring the underwater ecosystems of North Sulawesi, Prof. Dr. Nicolaas “Nico” Michiels stands out for his long-term dedication to documenting the extraordinary marine biodiversity of Bangka Island.

Professor Nico Michiels and His Quest for Fish Biodiversity

Based at the University of Tübingen in Germany, Prof. Michiels holds a Professorship in Animal Evolutionary Ecology.

Since 2016, he spent 30 weeks in Coral Eye to produce a baseline dataset of the incredibly diverse fish species diversity around Bangka Island with the aim to document ongoing change, communicate it to a wider audience and contribute to its protection.


From Dragonflies to Coral Reefs

Prof. Michiels’ scientific journey began far from the tropics, with dragonflies and questions about the evolution of reproductive strategies. Over the years, his focus expanded from freshwater insects to the life of coral reefs, leading him to study marine fish visual ecology and the evolution of red fluorescence in reef fishes.

The Bangka Reef Fish Archive

At Coral Eye Marine Outpost, Prof. Michiels leads an ambitious, long-term project to document all coastal fish species around Bangka Island, as well as nearby regions such as Lembeh, Bunaken, Siladen, and Biaro. Since 2016, he has conducted exhaustive underwater surveys across all coastal habitats that the area.

The resulting photographic database already exceeds 20,000 pictures. Each photograph serves as a record of presence, time, and location of a species, and will be used to track changes in species composition over time. His work already lists over 1,100 species, a number that continues to grow each field season.

The project relies on natural-light, flash-free underwater photography, depicting fish as they appear to divers and snorkelers. This approach not only preserves the authenticity of underwater coloration, but also makes field identification more accurate and accessible. All images are carefully verified and are being re-assessed over time. They are used to update “Reef Fish Trainers”. These are sets of pictures made available as digital flashcard decks and PDF booklets. They allow interested divers and snorkelers to memorize fish names and search for fish they have seen to improve their identification skills. Through Citizen Science platforms such as iNaturalist, data are made available to a global audience, expanding the project’s educational and scientific outreach.

Beginning in 2026, Prof. Michiels will extend his research to include specimen collection under a BRIN research permit, to search for more traits that can aid in visual identification of species that are difficult to distinguish in the field.

Back at home in Germany, these pictures (sometimes dozens to hundreds per species) are used in Bachelor and Master projects to identify new diagnostic traits than can be used for non-invasive, visual field identification of similar-looking fish species. Several such studies are currently in the pipeline and will be made publicly available.

Looking Ahead

By combining accurate species documentation with long-term observation, the project helps to identify biodiversity hotspots around Bangka and track human-induced changes, from fishing pressure to coral bleaching and waste accumulation. These insights are crucial for designing effective conservation and marine management strategies, particularly in defining e.g. no-catch zones and promoting sustainable fishing practices.

“Although fish are a renewable resource,” Prof. Michiels explains, “their management requires agreement and restraint. Our data can help inform local discussions to find optimal compromises between local use and protection for future generations.”

He sees the Coral Eye house reef as a prime example, a site with exceptional reef and fish biodiversity that could serve as a model for balanced conservation and sustainable marine use.

Additional Resources

Prof. Michiels’ ongoing work is also shared through digital tools that support fish identification and education. His comprehensive PDF catalogue of Bangka’s reef fish and digital flashcard decks are publicly available here. Similar materials for the Red Sea can also be found here (2015-2024). 

Anna Clerici