A global trade we still know surprisingly little about. The international trade in coral reef fishes has existed for almost a century. Today it supplies millions of home aquariums and public aquariums around the world, involving more than 60 exporting and importing countries. [1] Yet despite its global scale, one fundamental question remains surprisingly difficult to answer: Exactly which species are traded, in what numbers, and from where? [2]
Understanding the trade is the first step towards understanding whether it can be sustainable.
~ ~ ⚓ ~ ~
A Brief History
The trade in coral reef fishes began during the 1930s in Sri Lanka and the Philippines. By the 1950s, commercial air freight allowed tropical fishes to be transported internationally, and by the 1970s ornamental fisheries had become established throughout the Indo-Pacific. [3]
During the 1990s, marine aquariums evolved from displaying individual fishes to recreating entire coral reef ecosystems. Today the trade is a multi-billion-dollar global industry. [3][4]
The principal exporting countries remain Indonesia, the Philippines and Sri Lanka, while the major importing markets include North America, Europe and Japan. However, the importance of China and several other rapidly growing economies is increasing, although reliable trade statistics remain largely unavailable. [1][2][4]
~ ~ ⚓ ~ ~
How Big Is the Trade?
This is one of the most difficult questions to answer.
A United Nations report published in 2003 estimated that approximately 24 million coral reef fishes, together with millions of corals and marine invertebrates, entered international trade each year. These figures were largely based on voluntary declarations by traders. [3]
Our systematic review of the available scientific literature concluded that 28–30 million coral reef fishes are traded annually. Depending on how trade value is interpreted, this may represent up to 70 million wild-caught fishes each year. [5]
Despite decades of research, these estimates remain uncertain because no comprehensive global monitoring system exists. [5][6]
~ ~ ⚓ ~ ~
Did you know?
- Around 28–30 million coral reef fishes are traded annually. [5]
- More than 60 countries participate in the trade. [1]
- Millions of corals and marine invertebrates are traded alongside fishes. [3][5]
- There is still no comprehensive global monitoring system. [5][6]
~ ~ ⚓ ~ ~
The Biggest Challenge: Data Gaps
Perhaps the greatest challenge is not the size of the trade.
It is the lack of reliable information.
Many trade statistics are based on voluntary reporting, estimates or incomplete declarations. As early as 2003, major inconsistencies were already evident. Exporters reported that 43% of traded fishes originated from the Philippines, whereas importers declared that the origin of 81% of their imports was unknown. [3]
More than twenty years later, there is still little evidence that these problems have been resolved. [5][6]
Without accurate information on species identity, origin and source (wild-caught or captive-bred), assessing the sustainability of the trade remains extremely difficult. [5][7]
~ ~ ⚓ ~ ~
Why Monitoring Matters
It is remarkable that, in the twenty-first century, an entire group of more than 4,000 vertebrate species can still be traded internationally without comprehensive monitoring.
Scientists have called for improved monitoring for decades because good conservation begins with good information. [3][5][6]
Knowing
- which species are traded,
- where they originate,
- how many individuals are collected, and
- whether they are wild-caught or captive-bred
allows conservation decisions to be based on evidence rather than assumptions. [1][5][7]
~ ~ ⚓ ~ ~
A Solution Already Exists
One of the encouraging aspects of this challenge is that the necessary technology already exists.
The European Union and Switzerland use the Trade Control and Expert System (TRACES) to record the movement of live animals, animal products, plants and feed. Originally developed to protect animal and public health, TRACES could also provide accurate, real-time information on the international trade in coral reef fishes if adapted to record all traded species consistently. [7][8]
Rather than creating an entirely new monitoring system, improving an existing one may offer one of the fastest and most practical ways to improve transparency in the marine ornamental fish trade. [7][8]
~ ~ ⚓ ~ ~
What We Know — and What We Don’t
Our analyses of TRACES data have shown that Europe is currently one of the world’s largest importers of coral reef fishes by value. [1][2]
However, reliable information remains unavailable for many other important markets, including China, Japan and several rapidly growing economies in Asia, Africa and South America. [5]
Consequently, even after almost a century of international trade, we still cannot answer several surprisingly simple questions with confidence:
- How many coral reef fishes are traded globally?
- Which species are most heavily traded?
- Which populations are most affected?
- Is the trade sustainable?
Those questions remain at the centre of our research.
~ ~ ⚓ ~ ~
~ ~ ⚓ ~ ~
References
[1] Biondo, M.V., Burki, R.P., Aguayo, F. & Calado, R. (2024). An Updated Review of the Marine Ornamental Fish Trade in the European Union. Animals, 14, 1761. https://doi.org/10.3390/ani14121761
[2] Biondo, M.V. & Calado, R. (2025). Enhancing Wildlife Trade Monitoring in the European Union—No Need to Reinvent the Wheel. Ecology and Evolution, 15(9), e72090. https://doi.org/10.1002/ece3.72090
[3] Wabnitz, C., Taylor, M., Green, E. & Razak, T. (2003). From Ocean to Aquarium: The Global Trade in Marine Ornamental Species. UNEP-WCMC. https://digitallibrary.un.org/record/505321/files/fromoceantoaquar03wabn.pdf
[4] Rhyne, A.L., Tlusty, M.F., Schofield, P.J., Kaufman, L., Morris, J.A. Jr. & Bruckner, A.W. (2012). Revealing the Appetite of the Marine Aquarium Fish Trade: The Volume and Biodiversity of Fish Imported into the United States. PLoS ONE, 7(5), e35808. https://doi.org/10.1371/journal.pone.0035808
[5] Biondo, M.V. & Burki, R.P. (2020). A Systematic Review of the Ornamental Fish Trade with Emphasis on Coral Reef Fishes—An Impossible Task. Animals, 10, 2014. https://doi.org/10.3390/ani10112014
[6] Cohen, F.P.A., Valenti, W.C. & Calado, R. (2013). Traceability Issues in the Trade of Marine Ornamental Species. Reviews in Fisheries Science, 21(2), 98–111. https://www.tandfonline.com/doi/abs/10.1080/10641262.2012.760522
[7] Biondo, M.V. & Calado, R. (2019). Monitoring the Trade in Marine Ornamental Fishes through the European Trade Control and Expert System (TRACES): Challenges and Possibilities. Marine Policy, 108, 103620. https://doi.org/10.1016/j.marpol.2019.103620
[8] Biondo, M.V. & Calado, R. (2021). The European Union Is Still Unable to Find Nemo and Dory—Time for a Reliable Traceability System for the Marine Aquarium Trade. Animals, 11(6), 1668. https://doi.org/10.3390/ani11061668