Farmer Azizul Islam suffered his first stroke after a 2019 cyclone washed away shrimp worth 250,000 taka ($2,450) from his ponds on the southern Bangladesh coast.
The stress damaged his health, said the 34-year-old, who works on the vast stretches of low-lying land, known as ghers, used for aquaculture and rice paddies in Satkhira district.
"Then I had a second stroke this August as I had been fretting over how to manage my losses from the disaster and raise my two young sons," said Islam, sipping tea at a stall.
Experts say climate change is bringing higher sea levels and stronger storms, making the shrimp farming business harder in a region already plagued by environmental and social stresses.
Sardar Abdul Hamid, 38, runs a smallholding inherited from his father where he breeds shrimp and grows rice. But this year, rainfall has been meagre and the water level in his ponds has gone down, he said.
Export-led shrimp farming generates income but hurts ecology
Climate change drives rising salinity, stronger storms
Efforts to adapt, financial support not enough for small farmers
"I am worried that poor rainfall may affect the growth of shrimp and other fish," he said.
A warmer climate causes more evaporation, changing rainfall patterns, while sea-level rise increases salinity levels in farm water - factors that can affect yields, said Ahammed Zulfiqar Rahaman, a hydrologist and climate change expert at the Center for Environmental and Geographic Information Services (CEGIS).
By 2050, researchers estimate that sea-level rise will inundate significant parts of coastal Bangladesh where shrimp is bred, while higher temperatures affect pond water quality.
Climate change is also fuelling more powerful cyclones, while human activities have made the shoreline more vulnerable to their effects.
Tanzim Afroz, a climate-change law expert at Edith Cowan University in Australia, said large swathes of mangrove forests that usually act as a buffer against storm surges have been cleared to make way for shrimp ghers, reducing natural protection for local communities.
Mangroves are important for coastal ecology, supporting marine fisheries and protecting shores from erosion and extreme weather, she added.
Bangladesh's newly adopted National Adaptation Plan calls for an assessment of the risks climate change impacts pose to shrimp cultivation, to enable the identification of suitable zones where the business can be run sustainably in the future.
Already, growing climate risks and inadequate efforts to adapt the shrimp sector to new conditions are curbing its economic potential.
Shrimp exports from Bangladesh stood at $407 million in the financial year 2021-2022, but growth has stagnated in the past decade, blunting earlier expectations it would rapidly grow into a major export sector.
Shrimp cultivation is also an important source of income for coastal communities. But their business is threatened by increasing salinity and frequent climate-linked disasters that are damaging the fragile local ecology, experts say.
Most farmers use a traditional method of raising shrimp in paddy-fields in rotation with freshwater prawns, carp and crops.
In 2014, a national policy attempted to boost yields by increasing the share of more intensive shrimp farming, yet this method - often used on more saline land - still accounts for only about 5% of total shrimp production, said Sanjir Ali of LightCastle Partners, a Bangladeshi management consulting firm.
Large-scale intensive farming can have serious environmental impacts, degrading brackish-water habitats such as mangroves, mudflats and freshwater wetlands, said Md Kutub Uddin Arju, an activist with the ICCA Consortium, a nature protection group that works to promote indigenous and community rights.
Land-grabbing is another problem, as saltwater levels creep higher, encouraging more intensive methods of shrimp cultivation and conversion of paddy-growing plots into aquaculture farms.
Afroz, the climate law expert, said powerful locals have often exploited gaps in regulations and enforcement to take over land by force or stealth, and convert it into big shrimp farms.
This has fuelled tensions and conflicts that have driven out poor smallholder fishers and farmers, noted the ICCA's Arju.
Abdur Rahman, a sexagenarian farmer in a low-salinity area on the northern side of Satkhira, uses the lower-yielding traditional method and is happy with what he manages to earn.
"Our areas are relatively peaceful, but down in the highly saline coasts legal battles and conflicts over shrimp lands are pervasive," he said.
Gouranga Nandy, author of a forthcoming book, "Shrimps: Profit for Whom?", said the sector had been promoted as a better livelihood option before climate change began dominating policy talk and taking the blame even for pre-existing man-made problems.
For example, coastal salinity used to rise and fall in seasonal cycles but shrimp farmers have cut down embankments to let in more seawater and increase salt levels in their ponds, causing permanently high salinity in parts of coastal districts.
"No other crops can be grown there," said Nandy.
The problem is also affecting health, especially among women who need water for bathing and domestic use, and resulting in what activist Arju called "a fully-fledged public health crisis".
LACK OF HELP
In addition, farmers said they are not receiving enough aid to deal with worsening climate pressures and other challenges.
Sohel Shaikh, a young farmer in the southern port city of Mongla, suffered heavy losses during Cyclone Sitrang in October - and then a virus decimated his remaining shrimp stock.
"I hoped to receive support from the government to be back on my feet, but have not received any help," said Shaikh.
The 2014 national policy suggested that shrimp farmers hit by disasters should receive "financial incentives" to deal with losses, but did not provide details on the proposed assistance.
Sector consultant Ali said farmers should get help to prepare for climate change impacts, training in better methods, and easier access to finance and insurance.
Belal Hossain, a farmer in Satkhira, began his shrimp business with a 25,000-taka loan from a local non-governmental organisation (NGO), but has suffered losses, especially after the recent cyclone.
"I never had much luck getting finance from banks for my shrimp farm," he said.
He and other small-scale farmers lack financial knowledge and assets that can be used as collateral for bank loans, while financial institutions see the shrimp sector as risky.
Getting credit from NGOs or loan-sharks is easier, but the amounts are often smaller and carry high-interest rates.
Farmer Shaikh has been able to tap loans from banks and NGOs because he could mortgage his land. But the double hit from the cyclone and viral epidemic has now forced him to borrow from relatives and loan-sharks to repay installments, he said.
Farmers, meanwhile, have been testing ways of adapting to shifting weather patterns and rising salinity - with mixed results.
Some are trying to boost yields using new shrimp varieties, while others are branching out into crab-fattening.
Bangladesh has mostly focused on producing giant tiger shrimp up to now, but output has stagnated amid disease, disasters and limited access to finance and technology.
Shubrata Kumar Sarkar of MU Sea Foods Ltd, a shrimp processing farm that has tested a variety called vannamei, said the king prawns can tolerate changes in salinity and have good export potential.
"We plan to scale up our vannamei farming, and the government should encourage its cultivation," he said.
Other farmers are trying out ways to supplement their shrimp business, including crab-fattening.
Mud crabs are more resistant to climate stresses such as salinity and temperature variations, said Ali from LightCastle.
Farmers catch young crablets and artificially fatten them by feeding them a carefully managed diet in cages or pens.
Yet while the crab sector has some potential, it cannot substitute for shrimp production as crabs have little local demand and exports are limited, said Rahaman of the CEGIS.
Without hatcheries, farmers rely on catching wild crabs from near the Sundarbans, risking the eventual depletion of their stocks.
Experts said experiments like these are unlikely to improve the situation for communities unless decision-makers pay more attention to making policies work for farmers on the ground.
Ali said farmers lack power in a fragmented shrimp value chain dominated by middle-men and often cannot get their voices heard, despite being hit the hardest by disasters and disease.
"Farmers' livelihoods and well-being should be at the forefront of policy-makers' priorities," he added.