Interview: Professor Abdul Wahab
If we correct the mistakes, hilsa will return
After nearly a decade of rising hilsa production in Bangladesh, output has declined for two consecutive years. At the same time, the number of large hilsa is falling, while prices are rising. Professor Md Abdul Wahab, a renowned hilsa researcher and professor in the Department of Marine Fisheries and Aquaculture at Bangladesh Maritime University, spoke to Prothom Alo about the weaknesses in hilsa management and what needs to be done. The interview was conducted by Partha Shankar Saha.
Hilsa production in the country has been declining for two years. Production reached a record 571,000 tonnes in the 2022–23 financial year, but fell to around 500,000 tonnes within two years. Is this a temporary fluctuation, or a warning sign that hilsa stocks are facing a serious crisis?
Abdul Wahab: The surge began in 2016, when hilsa production reached 396,000 tonnes. After that, production increased by 10,000 to 20,000 tonnes each financial year. In 2018, a joint team of Malaysian and Bangladeshi scientists conducted a survey on the maximum sustainable fish production in the country’s rivers and sea.
We concluded that Bangladesh could harvest 600,000 tonnes of hilsa annually while remaining within the limits of sustainable production. However, taking a somewhat conservative approach, we said production would remain at around 550,000 tonnes, give or take. But we are now seeing the opposite picture.
The rising price of hilsa and the shrinking size of the fish have different implications. Higher prices indicate that supply is declining, while smaller fish indicate that the number and stocks of hilsa are on a downward trend.
At one point, we described Bangladesh as a global role model for the recovery of hilsa and river fish. That was because both the number and size of hilsa had increased. I believe the current problem is temporary. If we can identify the mistakes and take prompt action, hilsa will return.
You mentioned mistakes on our part. What exactly are they? Overfishing, behundi and fine-mesh nets, river pollution and submerged Chars are being cited as reasons for the decline in hilsa. Which factor is causing the most damage now?
Abdul Wahab: We have treated hilsa unfairly through our management practices, and hilsa has quickly responded by taking its revenge naturally. All the factors identified by scientists have had varying degrees of impact. However, in my view, the two biggest causes are catching mother hilsa during the breeding season and indiscriminate harvesting of jatka.
The way small hilsa and jatka are caught in Bangladesh should not happen in any country with effective fisheries management. Scientifically, a 22-day ban was introduced based on the optimal breeding period of mother hilsa. There are also government directives and operations by the fisheries and law enforcement agencies. However, effective public participation in management has not been established.
Over the past two years, there has also been some sloppyness compared to previous years in the 22-day programme to protect mother hilsa. The greatest damage is being caused by the use of illegal and fine-mesh nets during the ban period. As a result, the fry of other fish, shrimp and aquatic animals, along with hilsa, cannot escape the nets.
Trawling facilities have now also been installed on wooden boats operating along the coast. When jatka move out to sea, these boats catch large quantities of fish.
Silt is accumulating in various rivers and estuaries, including the Meghna and Tetulia, creating submerged Chars. Water flow and depth are declining. As a result, could hilsa be avoiding Bangladesh’s rivers and moving towards rivers in other countries or the deep sea?
Abdul Wahab: There is still insufficient scientific data on the extent to which submerged Chars and reduced water flow are harming hilsa. For now, this remains a hypothesis. There is also no evidence to support the conclusion that hilsa are avoiding Bangladesh’s rivers and moving into rivers in other countries.
We need to examine whether submerged Chars are obstructing fish movement in the rivers that remain important for hilsa. Before dredging rivers or deepening their beds, we need to assess the potential outcomes and sustainability of such measures. Decisions should be made only after conducting research through water and river experts.
There are concerns about power plants, industrial waste, the discharge of hot water and vessel movement near sanctuaries. To what extent has a direct link been established between these facilities and the decline in hilsa production?
Abdul Wahab: I believe that the direct or indirect effects of industrial facilities, power plants and vessel movement disrupt the arrival and breeding of mother hilsa, as well as the growth of their fry. However, I do not currently have research data establishing a direct link.
It is not possible to relocate industrial facilities, power plants or ports. They are necessary for the country’s development. Therefore, we must ensure coexistence. It is essential to ensure that hot water from power plants is not discharged directly into rivers. If coal or industrial waste is harmful, effective waste treatment systems must be in place.
We must ensure that one sector does not cause serious harm to another.
How are changes such as rising sea temperatures, irregular rainfall, reduced freshwater flow in rivers and increasing salinity affecting hilsa breeding and migration? Is there a need to reschedule the fishing bans?
Abdul Wahab: I believe climate change will affect the country’s fish, particularly hilsa. However, I do not think its impact has yet reached the level of an acute crisis. If water temperatures rise significantly, fish will naturally seek locations that are more favourable for them.
Climate change may alter the timing of hilsa spawning. The time when the fish reach reproductive maturity could shift earlier or later. The quantity of eggs and the survival rate of fry hatched from those eggs may also decline.
The 22-day ban in October to protect mother hilsa is still appropriate. However, research should be conducted to determine whether the period needs to be delyed slightly because of climate change.
It is not appropriate to limit the ban on jatka fishing in March and April to sanctuaries alone. Jatka fishing must be completely prohibited during these two months in all rivers and waterways where hilsa are found.
Various programmes, including long-term fishing bans, sanctuaries and assistance for fishers, have been in place for years to protect hilsa. Why, then, is production declining? Where are the weaknesses in management?
Abdul Wahab: Hilsa production increased in the past because of the combined impact of several initiatives. These included protecting mother hilsa for 22 days, maintaining an eight-month ban on jatka fishing, prohibiting fishing in sanctuaries during March and April, banning nets with mesh sizes smaller than 6.5 centimetres, and providing fishers with rice and other forms of assistance during the fishing bans.
However, there are weaknesses in three areas of management: scientific, social and administrative.
Five sanctuaries were designated in 2005. Another sanctuary, stretching 82 kilometres across the Hizla–Mehendiganj area and covering parts of the Kirtankhola, Arial Khan and Meghna rivers, was established in 2018. After protection was strengthened in that sanctuary, hilsa production increased significantly.
The problem is that the courses of the rivers have changed. Chars have formed in places where rivers once flowed, while previous chars have eroded and new river channels have emerged. Therefore, the boundaries and size of the sanctuaries need to be reassessed.
The Andharmanik River was once an important habitat for very young hilsa fry. Fry used to arrive there in November and December. However, pressure from ports, power plants and industrial facilities has increased around the Ramnabad Channel and surrounding areas. Industrial waste may also harm hilsa movement, breeding and the growth of fry.
Only a 20-kilometre sanctuary had been established at the mouth of the Padma. However, hilsa fry are now found across an area of nearly 100 kilometres. Therefore, reassessing the sanctuaries and redefining their boundaries is essential now.
Bangladesh is now importing large quantities of hilsa from India. More than 350,000kg entered the country through Benapole in July and August alone. Does this shift from being an exporting country to an importing one indicate a failure in hilsa management?
Abdul Wahab: It would not be right to view this as a flaw in hilsa management. I do not see hilsa arriving from India in a negative light. If we produce a surplus, hilsa will also be exported from here to India.
However, the country already produces sufficient quantities of fish such as rohu, catla, pangasius and tilapia. Hilsa has now become an expensive fish, like salmon. It is not a fish for everyday consumption. Therefore, even when there is a slight shortage of hilsa, we should rely on other locally produced fish rather than rushing to import it from India or Myanmar.
What does the government need to do now to achieve all three goals—restoring production, keeping prices affordable and protecting fishers’ livelihoods? How many years might it take to see results?
Abdul Wahab: First, public participation in protecting mother hilsa and jatka must be increased. Second, it will not be enough to provide fishing families with rice only during the ban periods. Measures must be taken to make them fully self-reliant.
Third, officials and members of law enforcement agencies working in the fisheries-rich southern region should be transferred regularly rather than being kept in the same place for long periods. If these measures are implemented properly, I firmly believe that hilsa will return within the next two years. For this part of Bengal is particularly well suited to hilsa.