Key Takeaways
- China’s prized hairy crab industry faces severe threats from extreme heatwaves and longer summers
- Farmers report three consecutive years of worsening weather conditions disrupting breeding cycles
- Higher temperatures create triple threat: slowed growth, reduced oxygen, increased bacteria
- 2023 harvest delayed as temperatures remained above 30°C until late October
China’s celebrated hairy crab industry is battling unprecedented challenges as climate change-driven heatwaves threaten the survival of one of the country’s most esteemed delicacies. Farmers at Yangcheng Lake in Jiangsu province report that the last three years have been their most difficult period in over a decade of cultivation.
“From 2022, it feels like the weather has been getting worse every year,” said 34-year-old farmer Xie Dandan, who prepares the crabs known for their sweet flesh and golden roe. “We’ve come to mentally prepare for these losses.”
The Climate Threat to Crab Survival
Unusually high temperatures and extended summers have disrupted breeding cycles since 2022, forcing farmers to develop new survival strategies. The Chinese mitten crabs, which can sell for hundreds of dollars in export markets like Singapore and Japan, face a triple threat from rising temperatures.
“Higher temperatures than usual spell a triple threat for the crabs by slowing their growth, reducing the amount of oxygen in the water and boosting growth of bacteria,” explained Kenneth Leung, a marine environment expert at City University of Hong Kong.
This year’s harvest hopes were dashed when summer temperatures around Suzhou’s famous crab-producing waters stayed above 30°C (86°F) until late October, significantly delaying maturity.
Farming Challenges and Adaptation Efforts
The labor-intensive cultivation process begins with growing larvae in ponds for about a year before transferring them to fenced lake farms for molting. Crabs typically molt about five times between March and the traditional late-September harvest start.
However, extreme heat proves particularly dangerous during molting periods, killing crabs as they shed their shells. In 2022, farmers resorted to dumping ice blocks into the water to cool temperatures.
Eastern China has experienced some of its hottest summers in recent years, with temperatures reaching 40°C (104°F) or higher for consecutive days as early as July. Weather officials confirmed 2023’s summer was China’s hottest since 1961.
Looking for Solutions
Professor Leung suggested selective breeding as a potential solution, choosing crabs with greater heat tolerance for reproduction. Authorities project a harvest of 10,350 metric tons this year, consistent with previous years except for 2022’s typhoon-impacted 9,900 tons.
Despite adaptation efforts, farmers recognize their limited control over environmental conditions. “We only can see whether the hairy crabs will be able to adapt,” Xie added. “If they can’t, then maybe this industry will just be eliminated. We can’t do anything about it.”
The situation highlights how climate change is affecting traditional food industries worldwide, with facing particular challenges from shifting weather patterns.
