The crucian carp is a species in the family Cyrinidae that is found in European and Asian freshwater lakes and rivers. With a typical weight of approximately 3 pounds (1.3 kilograms), the crucian is considered to be a medium-sized carp. This carp’s coloring is generally gold with a green back and red fins, but the shape can vary widely between slender and lean to perfectly round. This particular species is commonly farmed and consumed in Asia and Russia and is a favorite catch for European sports anglers. The crucian carp is also sometimes kept in ponds or aquariums as pets or ornamental fish.
Freshwater lakes, streams and rivers without a strong current are the crucian carp’s preferred habitat. These fish consume algae and other aquatic plants in addition to small whelk and other bivalves. The crucian carp has no stomach or teeth and chews food with gill rakers against a chewing plate.
A unique ability of the crucian carp is its capacity for survival despite being deprived of oxygen for months at a time. The species begins to store glycogen, an energy source, as water temperatures begin to cool with the onset of winter. The structure of the carp’s gills also change in a way that increases oxygen uptake. The crucian’s ability to survive without oxygen throughout the winter months has attracted the attention of many scientists who hope to apply this knowledge toward curing the oxygen starvation illnesses that can kill humans.
This carp species is a somewhat common ingredient in Chinese cooking. Since crucian carp is easily maintainable and relatively inexpensive to breed, it is a commonly fried and served as an entree. It is also stewed, marinated in vinegar or added to soup with tofu.
In Russia, the crucian baked in sour cream is a traditional dish. By baking the carp in sour cream, the flesh retains its moisture. The fish is often stuffed with dill and onion prior to baking. The crucian carp is bony but low in fat.
Sports fisherman in Europe often catch crucian carp in freshwater streams, rivers and lakes. Rods, reels and crucian carp floats are typical equipment. Hooks are baited and allowed to sit along the bottom until a carp bites. Bait can be purchased as a dried powder and mixed with water to make a paste but even snails can be used.
Although this species is not widely available for purchase because other species such as koi are more popular, crucian carp are sometimes found in freshwater aquariums and decorative garden ponds. It is considered to be a relative of the common goldfish though it lacks the same intense golden coloring.