Green fields, vast rivers, picturesque hills, and the world’s longest sea beach at Cox’s Bazar all speak of the rich ecological diversity of Bangladesh. Among its many water resources—rivers, canals, beels, lakes, and floodplains—the Halda River stands out as a unique and vital asset.
The Halda River is the only natural breeding ground in the world where freshwater fish species, such as carp, release their roe during a specific period of the monsoon. For over a century, this phenomenon has taken place annually, drawing interest from researchers, conservationists, and local communities alike.
This year, on Thursday night, the first batch of roe was released by mother fish at Amtua Point. The roe quickly spread across various parts of the river, marking the beginning of the seasonal roe collection. As news spread, hundreds of fishermen from riverbank communities set out with boats and nets, creating a festive atmosphere despite the adverse weather. Collection continued from the early hours of Friday until noon, with each collector harvesting three to four buckets of roe on average.
The Halda River’s unique ecosystem allows species like Ruhi, Katla, Mrigal, and Kalibaush to breed only under very specific conditions—typically between April and June, on nights of a full or new moon, accompanied by heavy rain and mountain runoff. These fertilised roe are taken to hatcheries, where they are preserved and developed into juvenile fish, supporting both conservation and the local economy.
Thanks to favourable weather this year—a combination of torrential rain, a full moon, and strong upstream water flow—the conditions were ideal for spawning. This has raised hopes among roe collectors and fisheries experts for a higher yield than in previous years.
Halda River is the only natural
breeding ground in the world
where freshwater fish species,
such as carp, release their roe
However, despite this natural bounty, the Halda River is in a vulnerable state. Indiscriminate catching of mother fish and dolphins, rampant sand extraction, unchecked river pollution from nearby industries are all threatening the river’s delicate balance. Illegal grabbing and dam constructions have narrowed its course, worsening the ecological damage.
Historically, around 76 species of fish were found in the Halda, but nearly 20 species, along with Gangetic dolphins and other aquatic animals, are now endangered. Immediate and effective action is essential to halt this ecological degradation.
To protect this invaluable resource, several initiatives have been undertaken, including training roe collectors in modern fry-breeding techniques and launching awareness campaigns to stop the killing of mother fish during peak spawning season. These efforts are expected to increase both roe yield and the overall fish population in the river.
The government has designated a 10-kilometre stretch—from Ramdas Munshirhat to Sattar Canal—as a protected breeding zone during the peak season. However, illegal fishing activities persist, even during the crucial roe-releasing period. This calls for intensified monitoring and enforcement by the authorities.
Upazila administration, naval police, and fisheries officials must maintain a constant presence along the riverbank, conducting regular drives to prevent illegal fishing and protect this national treasure. Reducing man-made threats—such as the hunting of roe-bearing fish and pollution—will be critical in ensuring the successful breeding of mother fish this year.
Additionally, roe collectors must be supported with all necessary facilities and supervision from local
administration and the Department of Fisheries. With proper care and sustainable practices, the Halda River—often referred to as Bangladesh’s "fish bank"—can continue to flourish and provide high-value indigenous fish species to the nation.
Preserving the Halda is not just a matter of environmental concern; it is also an investment in the country’s economic and food security. Protecting this unique natural breeding ground is our collective responsibility.
