Halda River known as Bangabandhu Fisheries Heritage is an important freshwater fish ecosystem of Bangladesh. In this ecosystem there are 93 species of small and large fish, shrimp and dolphin (Platanista gangetica).
Halda researcher Dr Shafiqul Islam confirmed this information on Tuesday afternoon.
Halda River is one of the most important natural fish breeding grounds for Majorcarp (Rui-rohita, Catla-Catla, Mrigel-Cirrhinus mrigala, Kalibause-Labeo calbasu). Halda River, one of the natural fish breeding grounds of the country, is currently in full breeding season of carp. This is when the eggs of fish hatch and the young fish are released into the river. The fish hatching season usually starts in April and lasts until June.
This river is a major river in Chattogram district. It is known for its biodiversity and is home to a variety of fish species. The river is also a major source of income for the people who live in the area.
Natural reproduction of carp fish occurs in Halda river due to interaction of various physical and chemical parameters of water (water temperature, water current, water level, electrical conductivity, turbidity, dissolved oxygen, pH etc.) with sufficient rainfall during new moon and full moon dates of April to June.
Due to lack of rainfall due to climate change, other important breeding parameters are not favourable, the desired eggs are not found in Halda even though the hatching period has already passed three times. If there is sufficient rainfall, salinity and other parameters will return to the ideal level and favorable environment will be created for carp mother fish to hatch in Halda.
The fish hatching season is also under threat from a number of factors. These include pollution, climate change, and overfishing. Pollution can harm the eggs of fish and make it difficult for them to hatch. Climate change can cause the river to become warmer and less hospitable to fish. Overfishing can deplete the fish population and make it difficult for the river to sustain itself.
The fourth spawning period of the mother fish starts from Tuesday and will continue till May 21. During this time, if there is enough rain with thunder and if the hill slope comes down, there is more chance of hatching of carp mother fish. However, if the environment is not favorable, i.e. if there is not enough rainfall, the carp mother fish will lay eggs during the full moon period of June 1 to 6 or the new moon from June 15 to 20.
