Crucian Carp Overwintering Secrets: Master Wintering Management Techniques

When the oxygen in the water decreases, in order to maintain normal metabolism, fish have to take in more water so they can breathe in more oxygen. However, the intake of more water affects the balance of salts in their bodies, increasing physiological stress. Therefore, in order to maintain normal physiological balance, most fish in winter do not rely on increasing their breathing rate to maintain normal physiological activity; instead, they automatically weaken respiration, and metabolism also begins to slow down. As a result, many fish become slower-moving in winter, and some fish even begin to hibernate. 

However, biologists have found that crucian carp remain relatively active in winter, even under the ice. Could crucian carp have some secret for overwintering? Yes. Scientists recently discovered that crucian carp rely on deformation of the gills to get through the severe cold of winter. The person who discovered this mystery is biologist Qiaolangde? Suolide of the University of Oslo in Norway. He placed some crucian carp into a water tank with an oxygen content lower than normal, and then observed that the gills of the crucian carp underwent a peculiar deformation, with the gill filaments splitting open, so that the respiratory surface area of the entire gill became larger. Suolide measured at the time that the respiratory surface area of the crucian carp's gills had actually increased to 7.5 times the normal value, which shows that the deformability of crucian carp gills is quite strong, and this is also an important reason for the vigorous vitality of crucian carp. We often find at aquatic product markets that even if there is a large basin packed densely with crucian carp, they are not very likely to die, while other fish species, when there are slightly more of them, easily die from lack of oxygen. This too is because crucian carp gills are good at deforming.

Is it only crucian carp gills that can deform? This cannot yet be determined with certainty, but scientists have so far discovered only that crucian carp have this ability. Therefore, some biologists have proposed that if the gene for gill filament splitting in crucian carp is researched and transplanted into other fish species, and transgenic fish capable of gill filament splitting are bred, perhaps freshwater fish farms would no longer have to rack their brains over how to get fish through the severe cold of winter.