Producers and exporters in Khulna are worried about falling production of shrimps, affecting exports from the region, for hurdles mainly stemmed from climate-induced changes in temperature.
In FY2021-22, only 33,271 tonnes of shrimp were exported from Khulna, a sharp fall from 42,489 tonnes in FY2011-12.
Industry operators say water bodies are losing their navigability, salinity level is fluctuating because of weaker force of natural high tides caused by moon’s gravitational pull, affecting the shrimp cultivation in the region, reports UNB.
Humayun Kabir, Vice President of Bangladesh Frozen Food Exporters’ Association (BFFEA), told UNB that it seemed good days are gone for the shrimp industry.
He said shrimp farming in Bangladesh began in the 1960s, and by the 1980s it grew up to an industry as commercial shrimp production led to the export of this fish species.
“But it seems like the heyday of the shrimp business is coming to an end. Production is getting lowered, while demand and prices are also falling. All in all, the situation is really dire for those associated with the shrimp industry,” he said.
Humayun also pointed out some reasons behind the decline in shrimp production including a shortage of shrimp minnows in the market.
“The few minnows that farmers can manage die due to high temperature of water. Minnows are very sensitive. They can’t survive without proper water, food and environment,” he said.
“Besides there are regular outbreaks of various diseases. That’s why the mortality of shrimps has increased manifold,” he added.
Golam Kibria Ripon, General Secretary of Khulna Division (Shrimp) Fry Trading Association, also said that salinity in the rivers in Khulna has become a major headache.
“Usually the water in the rivers of Khulna region becomes saline in January. Last year, salinity of the rivers was delayed to February. Lack of saline water during the harvesting period is affecting shrimp farming badly,” he said. “Although the rate of salinity used to be 16-18 ppt in May-June period, it has come down to 8-10 ppt nowadays.”
He said previously 60 to 70 per cent of minnows survived after releasing them in hatcheries, but now protecting even 15-20 per cent minnows has become a big challenge.
Ripon said that dredging of the rivers is a must to keep them navigable.
“As the water bodies are drying up due to climate change, finding water for shrimp farming is getting tough. Various species of shrimp minnows used to enter the enclosures during tidal surges in the past, which isn’t the case anymore,” he said.
He said the quality of soil beneath the rivers may have degraded too.
“All of these issues are making it hard for us to continue shrimp production,” Ripon added.
Joydeb Kumar, Fisheries Officer of Khulna District, highlighted various measures that the government has taken to protect shrimp farming.
“We’ve advised the farmers to increase the depth of their enclosures to keep water temperature normal. We’re also conducting drives to prevent the injection of harmful substances into the shrimps. Besides, we’re also conducting awareness-raising campaigns with cooperation from the shrimp farmers and manufacturers,” Joydeb said.
Dr Mostafa Sarwar, a noted climate expert and Head of Urban and Regional Planning department of Khulna University of Science and Technology (KUET), provided a scientific explanation behind the death of shrimp minnows.
“There is a difference between mature shrimps and their minnows regarding heat enduring capacity. Minnows can’t grow naturally in high water temperatures. Farmers release minnows to their enclosures in January-February when water temperature remains around 25 degrees Celsius. In March, water temperature rises to 27 degrees Celsius, which kills a large portion of the minnows,” Mostafa said.
Mostafa added that rising water temperature is also responsible for viral infections.
“The life cycle of viruses depends on temperature. Viruses present in the air are making hot water their new home, thus infecting minnows and killing them in droves”, Mostafa said.