There are clear signs that a tightening local supply of wild-caught fish is driving up prices and demand in China for species to replace local favorites like croaker, pomfret and flounder.

A shortage of fish in the East China Sea has worsened, according to officials at the Zhejiang Aquatic Products Processing and Marketing Association (ZAPPMA), a trade body representing seafood producers in Zhejiang province. “We don’t have the supply and consumers are having to adjust to frozen and even