© Zeb Hogan

Mekong fishes, vital for tens of millions of people and the health of the Mekong river system, are on the brink— with one-fifth facing extinction, warns a new report.

Mekong's Forgotten Fishes, a new report published by WWF and 25 local, regional and global Mekong-based organizations, details the extraordinary variety of fish species in the Mekong river. These dazzlingly diverse fishes are critical for the health, food security and livelihoods of tens of millions people across the region as well as the overall health of the river system, but they are under ever increasing pressure with one in five already threatened with extinction. 
The report details the extraordinary variety of fish species in the river – with at least 1,148 making the Mekong the third most biodiverse river after the Amazon and Congo. The Mekong is also home to one of the largest migrations on Earth in terms of numbers of animals, with an estimated 5 billion fishes on the move.
The report also highlights the critical role of all these fishes in maintaining the health of the Mekong River Basin and supporting societies and economies across the region. The Mekong boasts the world’s largest inland fishery, which accounts for over 15 per cent of the entire global inland catch, generates over US$11 billion annually, and is central to the food security and livelihoods of over 40 million people in communities across the basin.
But the Mekong’s fishes continue to be undervalued and overlooked by decision makers and at least 19 per cent of assessed species are now estimated to be heading towards extinction, with 18 species already listed as Critically Endangered by the IUCN Red List of Threatened Species. However, a staggering 38 per cent of species are considered Data Deficient, meaning too little is known about them to gauge their conservation status – and that the number of threatened species is likely far higher.
An unprecedented combination of threats is driving the decline in the Mekong’s fishes, including habitat loss, hydropower dams, conversion of wetlands for agriculture and aquaculture, unsustainable sand mining, invasive species – and the worsening impacts of climate change. Together, these threats are devastating fishes and fisheries with fish populations in Tonle Sap collapsing by 88 per cent between 2003-2019 and an estimated one-third fall in the economic value of the Mekong fishery between 2015-2020.
Urgent action is needed to reverse this alarming trend. Along with protecting and restoring freshwater ecosystems, Mekong countries should implement a transboundary Emergency Recovery Plan for Freshwater Biodiversity. This comprehensive 6-pillar plan, which includes letting rivers flow more naturally, improving water quality, and ending unsustainable exploitation of resources, can deliver solutions at the scale necessary to reverse the collapse in Mekong fish populations. Critically, local fishers and communities possess knowledge, expertise, and solutions — such as community Fish Conservation Zones — that have demonstrated success and which we can build on to help safeguard their fish and their river. However, local communities cannot safeguard the whole Mekong on their own — decision-makers need to factor in Mekong fishes and scale up effective actions to restore the health of the river and the invaluable life below its surface.
© Cambodia WWF / Gerry Ryan / WWF-Greater Mekong

"In Lao PDR, where Mekong fishes contribute 13 per cent of the country's GDP, we need to do more to protect the Mekong river's invaluable biodiversity. The impacts are visible across the country — from the communities we work with reporting unprecedented losses of fish catch every year, to the national extinction of freshwater dolphins in Lao PDR in early 2023. But there are signs of hope, which show Laos’ capacity to influence change: the forthcoming updated national law on aquatic and fisheries, with improved fisheries management approaches, as well as the successes of community-led Fish Conservation Zones are steps in the right direction." 

said Loris Palentini, Country Director, WWF-Laos.

"The threats are many — from illegal fishing, climate change, and rapid infrastructure development — and our window of opportunity to reverse the decline of these priceless fishes is limited. By scaling up successful actions and addressing these drivers of loss, we can restore the health of the river and all life below its surface, while contributing to sustainable development, food security, and poverty alleviation."