The world’s forgotten fish.

By Kathy Hughes, Freshwater Specialist, WWF-UK

© Thomas Cristofoletti / WWF-UK

You’d think it would be pretty hard to miss so many fish. Surely over 11 million tonnes of freshwater fish hauled out of the world’s rivers and lakes each year would attract some attention? Especially as they provide protein and livelihoods for tens of millions of people. But read most reports on the ‘global fish catch’ and you’ll realise they refer solely to ocean fisheries, even though freshwater fish represent at least 12% of the true global catch. It is a blinkered view that has wide-ranging consequences for the future of these fish, their ecosystems and the communities who depend on them.

But the reality is that few people ever stop to consider the life below the surface of the world’s freshwater ecosystems. Yet they are home to a wealth of amazing wildlife including approximately 15,000 species of fish[1]. That’s approximately 45% of all of the world’s fish species and one quarter of all vertebrate species in the world.

While some are tiny, others should be impossible to ignore — take the Beluga sturgeon, which historically reached over 7m in length (roughly the same size as a Great white shark), or the monsters of the Mekong such as the Giant freshwater stingray that can reach 5m in length, the Giant catfish, which grows to the size of a small car, and the wonderfully-named Dog-eating catfish, which feeds on the carcasses of large animals (including dogs). But freshwater fish, even these behemoths, are quite literally out of sight and out of mind and they have been mostly forgotten by the world’s decision makers.

© Zeb Hogan / WWF

This lack of attention has led to one third of all freshwater fish being considered under threat of extinction (IUCN, 2018) and freshwater ecosystems being the most threatened of the world’s major habitat types.

While such statistics have caused great alarm amongst the world’s conservationists and scientists, the world’s decision makers have not rushed to save these species. However, this may be soon set to change as a recent report[2] (http://www.fao.org/3/CA0388EN/ca0388en.pdf) from the United Nations Food and Agriculture Organisation (FAO) has presented evidence of the hidden value of freshwater fisheries. The report found that at least 12% (11.5 million tonnes) of all the fish caught in the world are wild freshwater fish. Approximately 90% of the 11.5 million tonnes of freshwater fish is for local markets, meaning that there is very little reporting of the catch. This has led to further research[3] which indicates that actual freshwater fish catch could be 65% higher than reported.

Figure 1. Global inland fishery catch (tonnes) per capita of population. Credit: FAO Review of the State of the World Fishery Resources, 2018

These fisheries constitute a significant part of people’s diets (Figure 1) — particularly in China, India, Bangladesh, Cambodia, Indonesia and Myanmar and across Africa. Furthermore the FAO found that 40% of freshwater fisheries comes from ‘low income food deficient counties’ (Figure 2) — highlighting their importance both for food security and nutrition. They also provide employment in fish capture and processing for up to 59 million people, and are estimated to be worth around US$43.5 billion.

Figure 2. Forty percent of inland fish capture comes from Low Income Food Deficient Countries. Credit: FAO Review of the State of the World Fishery Resources, 2018

But this is still a relatively small drop in the world’s economic bucket. So why should decision makers take note?

Historically the importance of freshwater fisheries has been under-appreciated, primarily because the extent to which this low-cost protein supports low income communities and boosts economies has been neither well measured nor understood. So decision makers have discounted their contribution. One clear example of the lack of recognition of the importance of sustainable freshwater fisheries is their lack of a specific mention in any of the 169 indicators of the UN Sustainable Development Goals (SDGs). Despite this there is now increasing awareness of the essential role they play in the achievement of the SDGs[4] particularly in relation to alleviating poverty, providing nutrition and achieving both economic and food security.

The general lack of recognition has also resulted in freshwater fish and their habitats being ignored in decisions about economic and infrastructure development, particularly when it comes to the construction of hydropower dams, which block fish migration.

Free-flowing rivers are essential for fish such as the Beluga sturgeon, Mekong giants and Dorado catfish to exist, let alone thrive. In fact the most productive freshwater fisheries are found within rivers that retain their natural characteristics and dynamic processes including healthy floodplains, connectivity with their flood plains, and up and down-stream connectivity because many river harvests are dominated by migratory fish. Yet, only a third of large rivers in temperate or tropical regions remain free flowing and many of those are now threatened by dams and infrastructure.

Freshwater fisheries are clearly one of the ‘hidden’ benefits of healthy rivers that have consistently been undervalued. The health and sustainability of freshwater fish stocks seldom appear to be factored into river development plans, yet wild freshwater fish are essential to both lives and livelihoods across the world and they are vitally important within low income food deficient countries; a food source that cannot easily be replaced[5].

Given this, the question should not be: why should decision makers take note of freshwater fisheries — it should be: how can they not?

© Thomas Cristofoletti / WWF-US

[1] Lévêque et al., (2006) Global diversity of fish in freshwater. Developments in Hydrobiology, Vol 198 pp 545–567.

[2] Review of the State of the World Fishery Resources (2018) Simon Funge-Smith, UN Food and Agriculture Organisation.

[3] Fluet-Chouinard, Funge-Smith & McIntyre (2018) Global hidden harvest of freshwater fish revealed by household surveys PNAS 115 (29) pp 7623–7628.

[4] Cooke et al. (2016) On the sustainability of inland fisheries: finding a future for the forgotten. Ambio Vol 45 (7) pp 753–764.

[5] Pittock, Dumaresq & Orr (2017) The Mekong River: trading off hydropower, fish, and food. Regional Environment Change DOI 10.1007/s10113–017–1175–8.