Carp

Typical of the wild form of carp are the large scales that cover the entire body. This is elongated and laterally flattened with an olive-green-brown back, which becomes lighter towards the belly. The dorsal fin extends over almost the entire back, the caudal fin is deeply forked. The head is elongated like a cone with small eyes and a trunk-shaped protruding mouth. Carp have no teeth on their jaws, but 3 rows of gullet teeth, which resemble molars. On the sides of the upper lip, carp have two pairs of barbels, the front pair being somewhat shorter.

The original distribution is in Asia around the Caspian Sea, the Black Sea and the Aral Sea and their tributaries, including the Danube, in the west and as far as China in the east.

Carp prefer warm stagnant to slow-flowing waters with plenty of plant growth. They also cope very well with low oxygen levels and acidification. Originally, most populations were therefore restricted to the middle and lower reaches of large rivers, although carp can also reach brackish water regions. As a result of stocking and breeding measures, the carp is now the most widespread edible fish.

In the late Middle Ages, not only the period between Ash Wednesday and Easter was considered Lent, but also every Wednesday, Friday and Advent. A total of around 150 days a year. As it was permitted to eat fish, the breeding and distribution of carp was mainly driven by monks and nuns. Carp are very insensitive to a lack of oxygen and heat, which is why they are predestined for keeping in shallow ponds. In the 19th century, carp were also introduced to countries such as the USA and Australia. Today, however, they are considered invasive in these countries as they have a negative impact on the local fish fauna and measures are being taken to decimate the carp populations.

Carp are considered to be peaceful fish. Young carp feed on zooplankton and plant seeds, later mainly on small bottom-dwelling animals such as insect larvae, snails and worms, but also small fish.

Carp spawn between May and July at a water temperature of 15-20°C. To do this, the males (milters) drive the females (rogers) into shallow, warm water zones with plenty of plant growth. The males poke the females in the flanks until they release the eggs into the water. The males then inseminate the eggs. The fertilized eggs attach themselves to aquatic plants. Depending on the water temperature, the larvae hatch after 3-5 days. For the first few days, they cling to the water plants and feed on the yolk sac. Then they sink to the bottom, as the swim bladder is not yet filled with air, and begin to feed on plankton. As they grow larger, they soon switch their diet to small bottom-dwelling animals.

The wild form of carp is considered endangered! Its widespread distribution today is mainly due to the stocking of cultivated forms by humans. Evidence suggests that carp were domesticated in China as early as around 500 BC.

The domestication of carp in Europe is attributed to the Romans, who caught spawning carp on the Danube as early as the first century AD and transported them to artificial pools to breed them there. Today's breeding forms, which are mainly the result of the efforts of medieval monasteries, are usually higher-backed, grow faster and have fewer or no scales.