Recent discoveries of ‘lost’ Mekong giant salmon carp renews hope for the fish – Image for illustrative purposes only (Image credits: Unsplash)
Cambodia’s Mekong River has yielded another surprise. A fish long feared gone from the country’s waters has now been recorded there for the fourth time since 2020. The Mekong giant salmon carp, a critically endangered species, appears to maintain at least one population in the lower basin despite years of absence from formal records.
A Species With Sparse History
The Mekong giant salmon carp was formally described only in 1991. In the following fourteen years scientists logged just twenty confirmed sightings across the middle and lower Mekong. After 2005 the trail went cold, and many feared the large predator had slipped into extinction in Cambodian waters.
Endemic to the middle and lower reaches of the river system, the fish can reach 130 centimeters in length. Its size and predatory habits once made it a notable part of the basin’s fishery, yet its rarity left biologists with little data on its current range or breeding habits.
Four Recent Records in Cambodia
Research led by Bunyeth Chan of Svay Rieng University changed that picture. A 2024 study documented three individuals caught by fishers between 2020 and 2023 in different stretches of the lower Mekong and its tributaries. Each fish was verified and added to the scientific record.
A fourth specimen was landed by a fisher on November 27, 2025. The capture was confirmed in a note published in the journal Oryx. Chan and colleagues stated that the observations show the species persists and that one or more populations inhabit the Cambodian Mekong and its tributaries.
Broader Meaning for the River System
The Mekong ranks among the world’s most productive freshwater ecosystems, yielding more than two million tons of fish annually with an economic value exceeding ten billion dollars. The return of a top predator like the giant salmon carp offers a small but tangible sign that parts of this system retain their capacity to support large native species.
Chan described the rediscovery as a reason for hope not only for this fish but for the entire Mekong ecosystem. The repeated encounters suggest that conservation attention and better monitoring can still yield results even for species that have gone unseen for years.
Questions remain about population size, breeding sites, and the precise threats that reduced the fish to such low numbers. Continued collaboration between researchers and local fishers will be needed to answer them.
What Comes Next
Each new record improves the chance that targeted protection measures can be developed. The species is still listed as critically endangered, and its future depends on maintaining the health of the river and its tributaries. The recent findings provide a narrow window for action before another long silence sets in.
