Zhoushan Three-Spined Swimming Crab

Zhoushan Three-Spined Swimming Crab

The Zhoushan Three-Spined Swimming Crab is a geographical indication certification trademark.

　　Geographical Scope

　　　　　There are many species of swimming crabs in the Indian Ocean–Western Pacific region, which are important economic crab varieties. Common types include the red-star swimming crab, the oceanic swimming crab, and the three-spined swimming crab.　　China has many regions that produce swimming crabs, and the waters near the Zhoushan Archipelago are one of the main production areas for swimming crabs in the country.

　　Specific Qualities

　　　　　　Swimming crabs, scientifically known as "Portunus," are commonly referred to as "white crabs" in some areas. They are named for their shell, which is shaped like a spindle. The central part of the carapace has three protrusions, hence the name "three-spined swimming crab."　　Zhoushan swimming crabs have tender, snow-white meat rich in protein, fat, and various minerals. During the winter migration season, these crabs are at their strongest, typically weighing around 250 grams, with the largest reaching up to 500 grams. Female crabs are filled with rich red roe, offering an exceptionally delicious taste. Swimming crabs can be eaten fresh, steamed, pan-fried, stir-fried, cut in half and stewed with bean paste, or used in dishes such as crab stir-fried rice cakes, salted vegetables, or tofu — making them a staple on the dining tables of coastal residents. They can also be cured by soaking fresh swimming crabs in brine for several days until edible, a method commonly known as "fresh wind-snatched crab." In the past, fishermen, due to the high yield of swimming crabs, would often select live crabs full of roe, extract the roe into bowls, and let it solidify through sun-drying and air exposure, resulting in "crab roe cakes" with a uniquely delicious flavor. However, this product was rare, and few had the chance to taste it.

　　Cultural Background

　　　　　　Swimming crabs inhabit shallow coastal waters, typically at depths of 10–50 meters, with the densest populations found in areas with muddy or sandy seabeds at depths of 10–30 meters. These crabs are sensitive to bright light and usually hide on the seabed during the day, venturing into the water column at night to forage. They have a particular preference for animal carcasses — a dead fish or shrimp can often attract a group of crabs competing for food. When farming swimming crabs, flow-through tanks equipped with oxygenation systems can be used, and shelters such as rocks and tree branches can be placed inside to reduce cannibalism. Male and female crabs are raised separately, fed mollusks, mixed shrimp, fish meat, and other foods. Swimming crab meat is delicious, primarily consumed fresh, but can also be refined into canned crab segments, dried crab meat, and more. Crab roe can be processed into seasonings, and crab shells can be made into chitin. In addition, the meat, internal organs, and shells all have medicinal uses. People often take advantage of their behavior by setting up drift gillnets with pre-placed bait such as fish slices and chicken at night in the sea to attract and catch groups of crabs. Trawling and baited fishing methods can also be employed, allowing anglers to catch larger live crabs.