Guebuem Kim

Abstract The swimming crab, Portunus trituberculatus, supports the world’s largest crab fishery. Hard-shell crabs have fully developed exoskeletons and are rich in meat, while soft-shell crabs, which have recently molted, contain less meat. To determine their nutritional status and feeding behavior, we measured amino acids (AAs), organic carbon (OC), δ13C, δ15N, and 210Po in the muscle of hard- and soft-shell crabs collected from the eastern Yellow Sea in May 2024.

The salinity ranged from 25.33 to 33.99 (avg. 29.79 ± 1.99) in the surface waters of the study region (Supplementary Table S1). The salinity distribution in the surface waters shows that the low-salinity (<31) water is widely distributed over the East China Sea (Fig. 1), due to the influence of CDW24. A patch of low-salinity water (<28) was observed in the southwestern region of Jeju Island, which seems to be detached from the Changjiang plume21,25.