- In India, the construction of barrages and dams on rivers has obstructed the movement of hilsa, a migrating fish.
- Under the Clean Ganga Mission, efforts have been made to conserve and increase the number of hilsa. Some of the experiments include releasing juvenile hilsa and their eggs in upstream of the Ganga river. Incentives are given to those who tag hilsas and provide information about their sighting.
- Bangladesh alone produces more than 80% of the world’s hilsa. India is ranked second. However, India produces only 10% hilsa as compared to Bangladesh and has to depend on the neighbouring country for supply. Experts say that India, Bangladesh and Myanmar will have to make joint efforts for the conservation of hilsa.
Prasanjit Mandal, 30, lives in Farakka, West Bengal, and his traditional line of work is fishing. However, these days, he also drives an autorickshaw to make a living. At times, he goes fishing with his friends in the Ganga river. Their aim is to catch a few hilsas; they are not interested in common fish. There is a reason for this. The hilsa, a popularly consumed fish in West Bengal, fetches them a good price.
When Mongabay-India met Mandal one afternoon, it was just after the monsoons. He had gone fishing with friends the previous day and they were fortunate to catch two hilsas. They sold the two for Rs. 2,500 and divided that among themselves. But it was a stroke of luck.
Explaining why hilsa is a good catch, Farakka-based Farooq Sheikh, who works in hilsa fish conservation, says, “A big hilsa, weighing one kilogram, is sold for Rs. 2,700-2,800. A smaller one, weighing 400-500 grams, fetches Rs. 700-800. So, catching a large hilsa is indeed a big deal.”
The cost of hilsa is determined based on the demand and the availability. Despite the high rates though, people flock to buy hilsa because of its health benefits. Mrunal S.K., a resident of Farakka, says, “Hilsa is a sought-after fish in every Bengali household.”
Hilsa population declining
A.K. Sahu, a senior scientist at Central Inland Fisheries Research Institute (CIFRI) in Barrackpore, Kolkat, told Mongabay-India, “Hilsa is a fast-moving migratory fish. Earlier, the fish would migrate up to Prayagraj (formerly Allahabad) in Uttar Pradesh. But, after the construction of the Farakka Barrage (on the Ganga in West Bengal), which began operations in 1975, hilsa migration came to a halt. When they could not migrate, their number went down in India.”
Even at a global level, the highly mobile hilsas are now found only in the narrow region of Bangladesh-India-Myanmar.
B.K. Das, director, Central Inland Fisheries Research Institute (CIFRI), told Mongabay-India: “The government of India, under the National Mission for Clean Ganga, (Namami Gange Mission) is taking all the necessary steps to ensure the number of hilsas goes up and the fisherfolk are important stakeholders in this.”
Officials at CIFRI informed Mongabay-India that the Ganga is home to 190 varieties of fish. A socio-economic assessment of fisherfolk living along the stretch between Farakka and Fraserganj in the lower stretch/stream of the Ganga revealed that varieties of fish like hilsa contribute 38.84% to their income. However, fisherfolk living in upstream in the stretch between Farakka and Prayagraj-Kanpur are deprived of hilsa. There was a time when hilsas were also found in Delhi and Agra.
As per CIFRI, the Farakka Barrage at the Ganga river is the primary barrier for the migration of hilsa fish. Hence, it would be convenient from a migration point of view if the hilsas are caught downstream and released upstream.
The CIFRI has released 74,962 juvenile hilsas from the Farakka barrage into upstream. The fisherfolk in Rajmahal, Bhagalpur and Baliya have confirmed the presence of hilsas in this stretch. Apart from this, 10.82 lakh fertilised eggs have also been released in the Ganga and a hatchery has been built upstream in Farakka.
However, an expert, sceptical of the experiment, told Mongabay-India, “The possibility of the survival of eggs is less than two percent. The tag recovery rate of hilsa is also low. In most cases, the water predators end up consuming the eggs. Besides, the survival of hilsa is also dependent on many environmental and geophysical factors like temperature, flow, and velocity.”
Favourable conditions for the breeding of hilsa fish
In the freshwater rivers, with an average temperature of 23 degree Celsius, eggs hatch in 23-26 hours. The temperature of the water plays an important role in their survival. Therefore, winter in the region is found to be the most suitable period for the breeding and movement of hilsa.
The average weight of hilsa after one year is 250 grams and it takes 3-4 years for the hilsas to weigh one kilogram. Conservation measures for the hilsa include creating awareness, ban on fishing during the breeding season, prohibiting the use of mosquito nets for fishing, and a ban on poisoning the rivers for fishing. According to CIFRI, between 2020 and 2022, it conducted 440 awareness programs in the stretch between Farakka and Prayagraj, in which a total of 18,326 fisherfolk participated.
The West Bengal government is also taking steps to conserve hilsas by declaring some river stretches as sanctuaries.
However, the Dakshin Bang Matsya Jeevi Forum, the main fisherfolk organisation in West Bengal, is not satisfied. Milan Das, the general secretary of the organisation, told Mongabay-India, “The West Bengal government is not taking serious initiatives for the conservation of hilsa. In this whole process, the fisherfolk have been made villains. The state government has formed only five hilsa sanctuaries with the IUCN (International Union for Conservation of Nature) funds and has said it would take action against fisherfolk if they enter the protected area.”
Impact of pollution on hilsa
River pollution affects the growth of the hilsa population to some extent, according to CIFRI. “Pollution causes stress to aquatic organisms such as fish. Although pollution is a broad term and includes industrial and agricultural pollution. It is difficult to ascertain the combined effect of all pollutants on fish reproduction. However, the stress caused by pollution definitely has a negative effect on reproduction,” officials said.
Mohammad Anisur Rahman, Director (admin and finance), Bangladesh Fisheries Research Institute, who is also a hilsa expert, tells Mongabay-India, “While the situation is better in Bangladesh, but the production of hilsa is declining due to several reasons including siltation, pollution, over-exploitation, and hunting of small hilsas. Climate change is also responsible for the decline in the number of hilsas.” According to Rahman, the use of dangerous fishing equipment is the reason for the decline in the number of not just the hilsas but many other fish as well.
CIFRI has also identified five major threats to hilsas, which include pollution – overfishing, obstruction by dams and barrages, river siltation, pollution, and climate change.
Reasons for hilsa decline from Farakka Barrage
A 2007 study titled Impact of Farakka Barrage on Hilsa Fisheries: An Overview states that after the Farakka Barrage was operational in 1975, the landing of hilsa in the middle stretch of the Ganga, that is, from Farakka to Prayagraj, decreased by 83.1% to 98.6%. At the same time, the landings downstream increased. In Prayagraj (Uttar Pradesh), between 1961 and 1970, 4.86 kg of hilsa was available per hectare. But after the barrage was built, the productivity dropped to 0.23 kg per hectare in the 1980s. Similarly, in Bhagalpur (Bihar), it decreased from 1.63 kg per hectare to 0.48 kg per hectare. Due to this, the livelihood of thousands of fisherfolk in Uttar Pradesh and Bihar has taken a hit.
According to the information received by Mongabay-India, right from the beginning, two gates of the Farakka Barrage have been marked as gateways for the movement of fish. Gate numbers 25 and 25A have been kept fish-locked since 1975. Many official letters have been sent to the government regarding this so that ways for conserving hilsas could be discussed.
In response to a Right to Information (RTI) application filed by this journalist, the Central Water Commission says, “Farakka Barrage has no fish ladder. There are two fish lock gates, and they are currently closed.” The Commission, in its reply, has said, “As per the records available in the office, this gate has been working since 1998. At present, this gate is being replaced by a new one and the replacement work is going on.” In response to a question about whether the movement of hilsa is getting affected due to the fish lock gate, the commission said, “There is no record available in our office that the fish ladder gate has affected the movement of hilsa.”
Nachiket Kelkar, head of the Riverine Ecosystem and Livelihood Program at Mumbai-based Wildlife Conservation Trust, told Mongabay-India in an email interview, “Re-operation of dams and barrages is the only way for hilsa to migrate upstream. In the areas where hilsa is found, they have already been over-hunted. Therefore, it does not seem that the income of fisherfolk can be increased with the help of hilsas. Continued management and regulation is essential for hilsa conservation, as they are reduced or limited to much of their historical range and density.”
Availability of hilsa and the dependence on Bangladesh
Hilsa has been one of the most important commercial fish in the Indo-Pacific region. Research suggests that Bangladesh, India and Myanmar account for more than 96% of the total hilsa fish produced in the world. A large part of this also happens in Bangladesh. According to a study, between 2010 and 2015, 86.7% of hilsas were produced in Bangladesh, 8% in India, and 4% in Myanmar.
So, should these countries make joint efforts for hilsa conservation?
“Definitely,” says Rahman, “This is a transboundary issue and India-Bangladesh-Myanmar will have to make joint efforts to protect them because for the hilsas to exist, fresh water, saline water, and marine water, all the three are required.”
The demand for hilsa is very high in India and it is dependent on Bangladesh for sufficient supply. Because the two countries share friendly relations, Bangladesh exclusively supplies hilsa to India, but there is a limit. According to the information received by Mongabay-India, the Bangladesh government had allowed the export of 2,450 metric tonnes of hilsa to India in 2022. However, Rahman told Mongabay-India, “Generally, hilsa is not being exported to any country presently. Hope it happens soon.”
How does Bangladesh conserve hilsa?
Rahman informed Mongabay-India that four strategic measures are important for hilsa conservation in Bangladesh – protection of juvenile hilsas by setting up sanctuaries; facilitating the conditions around the breeding or spawning sites during their breeding season and conservation; ban on fishing in the sea for 65 days (May 20 to July 23) every year; and subsidy to the poor fishing community at the time of breeding and nursing of hilsa.
In 2008-09, 2.98 lakh metric tonnes of hilsa were produced in Bangladesh. In 2019-20, the number has almost doubled to 5.65 metric tonnes.
This story was first published in Mongabay-Hindi.
Banner image: Hilsa Breeding Center at Farakka. The hatchery has been built upstream by taking in possession of two ponds from the authorities. Photo by Rahul Singh.