STAFF CORRESPONDENT, Ctg

Continuous rainfall, hill runoff and lightning have triggered carp spawning in the Halda River, with collectors reporting the presence of eggs at multiple points after the ebb tide began yesterday afternoon.

Brood fish usually spawn in the river stretch between Madunaghat and Sattarghat in Raozan and Hathazari upazilas.

District Fisheries Officer Salma Begum said collectors had already begun finding eggs along different points of the river. “Brood fish released eggs on Wednesday and in the early hours of yesterday. However, the volume of collection remains low so far,” she said.

Egg collector Abul Fazal from Gorduar in Hathazari said quantities remained small despite spawning activity.

“Although brood fish have released eggs, the quantity collected is still very small. There is a possibility of full-scale spawning at night,” he said.

Collectors have begun gathering eggs and transporting them to hatcheries in buckets, Salma said, adding that spawning had yet to reach full intensity.

Carp in the Halda typically spawn between Chaitra and Ashar, particularly on full and new moon nights when heavy rain, lightning and hill runoff coincide.

Originating in Khagrachhari, the Halda flows around 98 kilometres through Fatikchhari, Raozan and Hathazari before joining the Karnaphuli River.

Prof Manjurul Kibria, a Halda researcher and vice-chancellor of BGC Trust University Bangladesh, said a “spawning festival” was likely to occur between 7:00pm and 8:00pm with ebb tide conditions prevailing.

About 400 collectors gather eggs from the river each year, supplying fry to hatcheries nationwide, though several thousand people are involved in the sector.

The Halda is the only natural river in the country where fertilised carp eggs are collected directly, and its fry are widely valued for rapid growth, he added.

According to the fisheries department data, egg collection stood at 25,536kg in 2020, 8,500kg in 2021, 14,664kg in 2023, 1,680kg in 2024, and about 14,000kg in the most recent year.