The National Institute of Fisheries Science (NIFS; President Kwon Soon-wook) projected this fall’s West Sea blue crab catch to be 12,000 to 16,000 tons, or 69-92 percent of last year’s catch of 19,423 tons. Compared with the five-year average, the catch is projected to stand at 92-123 percent.

*West Sea blue crab catch during the fall fishing season: (’15) 8,615 tons, (’20) 9,827 tons, (’24) 7,885 tons, (’25) 17,423 tons  

NIFS attributed the decline in blue crab catch not to a decrease in the crab population but to a weakening of the Yellow Sea bottom cold water mass. According to NIFS, this causes blue crabs to disperse across the entire West Sea, significantly reducing catch efficiency per net.

The stock status of West Sea blue crab this year is assessed as stable and healthy. The stronger Yellow Sea Warm Current (YSWC) last winter boosted crab recruitment, and a bottom trawl survey that the institute conducted in July found an average crab distribution density of 345 kg/㎢, about 2.4 times higher than the 146 kg/㎢ recorded in 2025. 

The West Sea Fisheries Research Institute of NIFS has published a blue crab fishing outlook for every spring and fall season since 2011 to support sustainable fishing operations. To improve forecast accuracy, it uses a machine learning-based AI prediction model trained on blue crab stock and catch volumes, transport volume of  YSWC in winter, coastal water temperatures, etc. 

“In recent years, the blue crab stock in the West Sea has remained at a relatively sustainable level, but catch efficiency is expected to decline due to the dispersal of blue crab across fishing grounds,” NIFS president Kwon Soon-wook said. “We will concentrate our research capabilities on reducing uncertainty in the field based on solid scientific evidence.”