Crucian carp in Dongping Lake

Dongping Lake bream

　　Dongping Lake bream, also known as “Wuchang fish” or “Changchun bream,” and referred to by fishermen as “square fish,” belong to the class Actinopterygii, family Cyprinidae. They are one of the premium fish species in the lake. The period before 1970 was their peak production time. Experienced fishermen note that the best time for catching them is during the early cold of autumn. As the fishing proverb goes: “When people feel cold, they wear coats; when fish feel cold, they head for the grass.” In cold weather, bream tend to gather in grassy areas to keep warm. In the 1960s, fishermen from Laohu Village, Laohu Town, once caught nearly 40,000 kilograms of fish in an area of about 40 acres covered with aquatic plants, most of which were bream.

　　Dongping Lake bream have a laterally compressed body, with both the belly and back slightly protruding, giving them a roughly diamond shape. They typically grow to around 30 centimeters in length, are silver-gray in color, and have fleshy keels along the entire ventral surface. Their heads are small, with keratinized projections on the front edges of the upper and lower jaws. The dorsal fin has hard spines, and the anal fin is elongated. Males reach sexual maturity at one year old, while females mature at two years. Spawning occurs annually between May and June, with the eggs floating and inhabiting the middle to lower water layers. Juveniles are omnivorous, but after one year, they prefer to feed on aquatic and terrestrial plants. Their flesh is tender, rich in fat, and considered superior to that of crucian carp. Before 1970, the largest individual caught in the lake weighed over 1 kilogram, accounting for 2–3% of the total fish yield. After 1985, due to overfishing, their yield significantly declined, necessitating protective development measures.