For more than a decade, 34-year-old cultivator Xie Dandan has tended one of China’s most prized crustaceans: the hairy crab, whose delicate sweet flesh and golden roe are considered a seasonal culinary treasure. But she now finds herself mentally bracing for loss, labouring amid tanks of the furry-clawed crabs while confronting a new reality of unprecedented heat and disrupted cycles.
Her concern is not isolated. Farmers around Yangcheng Lake in Jiangsu province say that since 2022, abnormally high temperatures and prolonged summers have upset the delicate growth and harvesting rhythm of Chinese mitten crabs — the species that produce the celebrated hairy crab.
Experts say three interlinked threats are now converging on the industry: higher water temperatures slowing molting and growth; reduced oxygen levels impairing health; and a boost in harmful bacteria thriving in warmer waters. According to marine environment specialist Kenneth Leung of the City University of Hong Kong, such conditions “spell a triple threat” to the crabs.
In recent years, eastern China has seen not only higher peak temperatures — including stretches of 40 °C or more — but also longer summers, pushing water temperatures above 30 °C in harvest zones such as Suzhou, where the species are prized for taste. Farmers say this delayed maturity at a time when harvesting schedules are tightly timed and optimised for quality.
The traditional path for raising the crabs involves about a year in ponds for the larvae, followed by transfer into fenced sections of the lake where they molt roughly five times from March to late September — ahead of the season when they are harvested. Huge disruptions to this cycle now threaten both yield and quality.
Adding to the challenge, in 2022 farmers even resorted to dumping blocks of ice into the water to cool the tanks — a stop-gap measure that underscores the urgency of the situation.
Despite the severity of these pressures, the authorities currently expect the yield at Yangcheng Lake this year to reach around 10,350 metric tons — effectively matching production in previous years, apart from last year’s dip to about 9,900 tons when a major typhoon struck.
But farmers remain cautious. Xie warned that if the crabs cannot adapt to worsening conditions, the entire industry might face elimination. “We only can see whether the hairy crabs will be able to adapt, and if they can’t, then maybe this industry will just be eliminated. We can’t do anything about it,” she said.
What’s unfolding at Yangcheng Lake is emblematic of broader climate-linked shifts that can corrode traditional food industries reliant on finely tuned ecological cycles. In the case of the hairy crab — a seasonal delicacy with both domestic and international culinary worth — the stakes reach beyond farmer livelihoods to export potential and gastronomic heritage. The high export value of the species, sometimes selling for hundreds of dollars per four-crab set to markets including Singapore and Japan, underscores the economic dimension of the risk.
As China grapples with its hottest summers since the 1960s combined with shifting rainfall patterns and extreme weather events, the reservoir of business resilience and adaptive innovation will be tested. Options such as selective breeding of higher-temperature-tolerant crabs have been suggested — but these are long‐term and complex solutions.
For now, farmers like Xie are left watching the weather, hoping for manageable conditions and scrambling to adjust practices — even as they acknowledge they’re largely “at the mercy of the sky.”
In short, what was once a reliably timed and predictable harvest is now at risk of being undone by an increasingly unpredictable climate, placing one of China’s most loved seasonal treats—the hairy crab—on uncertain footing.
