Can hilsa be farmed in pond as hobby?

Following the first part:

Known nationally as a Hilsa researcher and expert, Dr. Md. Anisur Rahman has served as the Director of the Finance and Administration Department at the Bangladesh Fisheries Research Institute in Mymensingh. He was also the Chief Scientific Officer of the Riverine Fisheries Research Center in Chandpur and is now in post-retirement leave (PRL). He has played a significant role in Hilsa research and in implementing and enforcing measures to protect juvenile Hilsa (jatka) and spawning mothers. Recently, he shared his insights with Views Bangladesh on why Hilsa has become integral to Bengali culture, economy, and politics, and what steps we must take to protect this prized fish. KM Zahid conducted this two-part interview. Here, you can read the concluding part.

Views Bangladesh: Research shows that fewer Hilsa are appearing in rivers. What are the main reasons for this decline in river or estuary production?

Dr. Anisur Rahman: Hilsa production is increasing overall, yet there are times when we see fewer Hilsa in rivers or estuaries than before. There’s some truth to this, though Hilsa is still quite abundant in the sea. The problem lies in river pollution, as most cities, towns, and industries in Bangladesh are situated along rivers, and the waste from these urban areas is polluting our rivers significantly. This includes sewage, toxic industrial dyes, and waste, which not only threaten Hilsa but also endanger other fish and aquatic plants, devastating river biodiversity.

For this reason, wastewater from factories should be treated in effluent treatment plants (ETPs) before being released. Is this happening in practice? Not really. It is the responsibility of the current interim government to take effective actions, regardless of the stature or power of individuals involved, to protect our rivers. If we do not reduce sand mining from rivers and free rivers from encroachment, we risk losing not just Hilsa but all aquatic life.

Views Bangladesh: Why is Hilsa considered a "mysterious" fish? And why is the male Hilsa said to be even more mysterious? How can one tell male and female Hilsa apart, and do they engage in mating?

Dr. Anisur Rahman: People are often drawn to beauty, and the same is true for fish—people gravitate toward attractive fish in the market. Hilsa has an interesting trait: within a school of Hilsa, the ratio of males to females can vary by age, size, and location.

As Hilsa migrate upstream in rivers like the Padma and Meghna, they are typically smaller, and studies show that around 60% of these fish are male, while 40% are female. When they gather in the Meghna near Chandpur, they are about 24-28 cm long, with roughly a 50-50 male-to-female ratio.

However, when they move to estuaries near the sea to spawn, 80-90% of them are female. So, where do all the male Hilsa go? This is the mystery of male Hilsa. Interestingly, males of certain species like Tenualosa ilisha and Tenualosa toli can undergo sexual transformation. Males are generally slimmer and less vibrant, while females are plumper and brighter. Males, after mating, either get caught or become less active, which is why fewer of them are seen. Moreover, many males adapt to resemble females to achieve the same desirable traits.

Views Bangladesh: Why are male Hilsa rarely seen in the market? Where do the caught male Hilsa go?

Dr. Anisur Rahman: After releasing sperm in the swirling river waters and females releasing eggs nearby, both male and female Hilsa appear long, thin, and dull. If fishermen catch these fish, they don’t bring them to market. Instead, they may consume a few or give them away, and if there’s a large catch, they salt and preserve them as ‘nona Hilsa’ (salted Hilsa), which we see in markets throughout the year.

Views Bangladesh: Why is Chandpur often called the "home of Hilsa"? Where is Hilsa’s actual home?

Dr. Anisur Rahman: Hilsa is actually a symbol of Bangladesh. Many people say, "Sir, you’ve lived in Chandpur for so long; Hilsa is found only there and tastes amazing." Yes, Hilsa is indeed found in Chandpur, and the Hilsa there is quite tasty. But I also emphasize that Hilsa is found in other areas like Barisal, Bhola, Patuakhali, Cox’s Bazar, and Chattogram. Hilsa spawn, grow, and are caught by fishermen in these regions as well. Though Hilsa can be found in other countries, nowhere is it as flavorful and delicious as in Bangladesh, thanks to the unique water, climate, and ecosystem here. Therefore, I say Hilsa’s true home is not just a single district or place but all of Bangladesh’s waters.

Views Bangladesh: It’s often said that "Hilsa dies after two and a half flops." Why does it die so quickly after being caught?

Dr. Anisur Rahman: That’s an interesting question. There’s truth to the saying that Hilsa dies quickly on land, but it’s not entirely accurate. Hilsa require a high-oxygen environment to survive. After being pulled from the water, they struggle intensely, becoming weak and fatigued. In my experiments, I’ve placed them in water treated with potassium permanganate, which helps them survive for up to 8-10 hours in a full bucket or tub. Hilsa simply need more oxygen to live; unlike local fish like koi or shing, they lack the respiratory adaptations to survive longer outside water.

Views Bangladesh: You mentioned attempts at farming Hilsa in ponds. Is it feasible to farm Hilsa in ponds? What does research say?

Dr. Anisur Rahman: Pond farming of Hilsa is possible, though not on a commercial scale—rather as a hobby. The first trial was in 1988 in two ponds at the Chandpur Fisheries Institute, where we observed Hilsa for 12 months from March 1988 to February 1989, achieving a survival rate of about 50%. In 2010, we started another trial with three ponds, each at different depths, where we stocked about 2,200 Hilsa fry.

By maintaining artificial water flow and feeding the fry, we could keep them alive, but they grew only 50-100 grams in the first year and didn’t develop normally. After observing them for a while, we concluded that commercial pond farming is not viable. Although we can keep them alive with artificial conditions, their taste, growth, and reproduction aren’t like river fish. Thus, instead of focusing on pond farming, we should strive to protect their natural habitats—rivers and estuaries—to fulfill our desire for Hilsa.

Views Bangladesh: After so many years of research, what is your relationship with Hilsa? How do you feel about eating Hilsa?

Dr. Anisur Rahman: Whenever I hear "English" or even "police," I think of Hilsa. So, you can understand how ingrained it is in my mind and life! Over 33 years, Hilsa has been my world. When I handle, dissect, or study them, it feels like a conversation. Though I’m officially retired, Hilsa has never left me. Researchers, officials, and students still contact me from around the country with questions about Hilsa.

I am also often invited to seminars, symposia, and state meetings on Hilsa. It brings me joy. In the past, my family used to complain that I was so preoccupied with Hilsa that I didn’t spend time with them. But now, seeing the importance of Hilsa to our culture, the economy, and even diplomacy, they feel proud. Hilsa is now a symbol of Bangladesh’s identity and pride.

Views Bangladesh: Thank you.

Dr. Anisur Rahman: Thank you.

Frst part:
We must nurture Hilsa to keep it in our waters