The ilish, known internationally as hilsa or hilsa herring, is a species of fish in the family Clupeidae, closely related to the herring. It is the national fish of Bangladesh and the state fish of West Bengal in India, and it holds a place in Bengali food culture that few other ingredients can match.
As of 2023, Bangladesh produces 97% of the world’s total ilish supply. The fish accounts for roughly 12% of Bangladesh’s total fish production and contributes about 1.15% of the country’s GDP. Around 450,000 people depend directly on catching hilsa for their livelihoods, while an estimated four to five million more are indirectly tied to the trade. In August 2017, the Department of Patents, Designs and Trademarks formally registered ilish as a Geographical Indication of Bangladesh, cementing its status as a product uniquely associated with the country.
The fish goes by many names across the region. In Assamese, Bengali, and Odia communities in India it is called ilish. In Iraq it is known as sboor, and in Malaysia and Indonesia it is commonly called terubok. In Myanmar the Burmese name derives from a Mon language word, with both meaning simply “fish.”
Female hilsa grow larger than males, reaching up to 55 cm in length, while males do not exceed 46 cm. The fish matures by the end of its first year or the start of its second. Alive, it has a striking silver body shot through with gold and purple.
Hilsa is an anadromous fish, meaning it lives in coastal marine waters but travels up rivers to spawn. It ascends rivers in Bangladesh, India, Pakistan, and Myanmar by 50 to 100 km during the southwest monsoon season, roughly June to September and again January to April. It is also found in the Persian Gulf, including the Tigris and Euphrates rivers in Iran and southern Iraq. The species filter feeds on plankton, diatoms, green algae, and crustaceans, with juveniles relying more heavily on crustaceans than adults.
Despite numerous attempts since the 1900s, no one has yet successfully completed the hilsa’s full life cycle in captivity, making large-scale aquaculture of the fish still out of reach across South Asia.
Image: Wikimedia Commons / Roddur 123 (CC BY 4.0)