Protecting a Precious Resource – Ilish
Referred to locally as Ilish, Hilsa Shad is undoubtedly the most popular fish in Bangladeshi cuisine, and is an important source of nourishment throughout the country. The Bay of Bengal is home to three species of Hilsa Shad – Hilsa kelee, Hilsa toil and Hilsa ilisha. Unlike most tropical water fish species, Hilsa ilisha is anadromous – migrating long distances up rivers to spawn – and is caught at various stages of its lifecycle, both in the Bay of Bengal and along the many rivers of Bangladesh. The other two species – Hilsa kelee and Hilsa toil – are not found in fresh-water rivers, but remain in the marine waters of the Bay of Bengal.
At the start of the south-west monsoon and annual flooding, mature Ilish travel hundreds of kilometers upstream to spawn. Measuring between 30 and 55 centimeters in length, Ilish are known to produce between a hundred thousand and two million eggs. These are deposited in fresh water where they are fertilized, hatching out within twenty-three to twenty-six hours depending on water temperature. Juvenile fish, which are known locally as jatka take up to six months to travel downstream to the Bay of Bengal. Along the way, they feed and grow – and are caught by fishermen, particularly in the deltaic rivers of Padma and Meghna. It is common to find a plentiful supply of jatka for sale between February and May, with the juvenile fish measuring between 4 and 15 centimeters in length. The Ilish that make it past the fine-meshed nets used by fishermen to capture them in the rivers, will spend up to two years maturing in the Bay of Bengal as they feed primarily on plankton. Upon reaching maturity they make their way upstream to spawn – and so the cycle continues.
In an effort to prevent over-fishing and the associated risk of depleting this precious resource, Bangladeshi authorities declared a Jatka Preservation Week in April 2012, with the additional measure of a ban on catching jatka between November and May. This would allow greater numbers of the juvenile Ilish to reach the Bay of Bengal, where they could reach maturity and keep the cycle going. A recent report noted, however, that the ban has had little effect, despite the fact that the government has provided food grains to hundreds of thousands of families reliant on the fishing trade for a living. Nevertheless, efforts to curb over-fishing will continue to be made so that future generations can also enjoy the delights of Bangladeshi cuisine, with Ilish as the favored ingredient.