Release eggs before rain; fishermen see salty water intrusion as reason
Even in weather adverse to laying eggs, a number of fish species yesterday started releasing spawns in the Halda river at Hathazari and Raozan upazilas, the only natural fish breeding centre of sweet water in the subcontinent.
Mother fishes depend on special factors like water temperature, specific water current, rain and lightning to lay eggs.
But local fishermen and experts said they released eggs in the river although nothing like that happened yesterday.
The fishermen have begun collecting the spawns from the river but they fear that the spawns might be carried away by the high tide.
Terming it an “abnormal incident”, Md Manjurul Kibria, assistant professor of Zoology department of Chittagong University said, “No parameter of our observation indicates such happening.”
According to him, this unusual incident might be an impact of climate change. He, however, said they will be able to give specific reasons after observing the situation for a few days.
Prof Manjurul advised the spawn collectors to preserve the eggs in the sweet pond water.
Spawn collector said the indigenous fish species release spawns during Chitra, the Bangla month when it thunders and rains.
Seeing the movement of species like Ruhit, Katla and Mrigel in the river and some thundering rain in the area last month, spawn collectors expected the mother fishes to release eggs, but they did not.
They said they were astonished seeing some eggs yesterday.
“Our net, boat and the traditional small mud holes where we keep the fertilized eggs were not ready”, said a fisherman.
In the 1960s and 70s, Halda fish used to meet the demand of eggs for two-thirds of the country’s ponds, experts say.
Now the quantity of eggs has reduced significantly due to illegal fishing. Only 20 kgs of fish fry were collected in 2004, a steep decline from the 2,500 kgs collected in 1946, they add.
Courtesy of The Daily Star