What the carps eat?

French ichthyobiologists examined the stomach contents 1398 carps from stagnant waters. Read on, what these fish eat most willingly.
Carps are not, as previously thought, typical herbivores. The latest research proves, that they are omnivores and show a particular liking for eating animal food. Food of animal origin is sometimes from 75 do 95 percentage of carp's total nutritional requirements. Carps are food active mainly at night, and in the early morning and evening hours. Like other quiet feeding fish, they eat the most food in summer. In winter or late fall, when the water temperature drops below 10 degrees, the food requirement of carp is clearly decreasing. In water with a temperature below 6 degrees, the carp almost completely stop feeding.

Daphnia in the stomach

In spring, an animal plankton is a very important item in the carp diet. All adult fish eat it, however, seldom do animal plankton constitute more than 10 percentage of total food weight. Zoo-plankton should therefore only be regarded as a supplement to the main food, which does not change the fact, that some three-year-old carp can eat up to 600 g laurel (daphnia). It is true that in summer, many plants have been found in the stomachs of carp (usually more developed, deciduous), however, plant food is not the carp's main food. It is only during the summer heat that carps sometimes fill their stomachs with only plants, however, at other times of the year, plant-based food rarely constitutes more than 10 percentage of the total food weight eaten by the fish. Eating a lot of plant food can also be explained by the lack of natural animal food in the water. However, it should be noted, that with the exception of the amur, hardly any other species of fish eats so many plants, like carp. The main component of carp's diet are bloodworm larvae. The presence of bloodworms was found in the stomachs 8, on 10 carps tested. These larvae make up about a quarter of the total food eaten by carp. Volunteer larvae live in sediments of organic debris that decompose on the bottom. Foraging carps are often sucked into their mouths (together with bloodworms) rotting parts of plants and swallow them. In one liter of decomposing plant residues, sometimes even up to 4.000 pieces of bloodworm larvae. It explains it, why both of these types of food are found in the stomachs of carp so often and in such large quantities. Carps are among the few bottom fish, which are looking for food in the silt even with very low oxygen content in the water.

Craving for larvae

Right after bloodworm larvae, the favorite food of carp are water snails and other small mollusks. This food was found mostly in the stomachs of adult fish, but, when bloodworms constituted at most a quarter of the volume of the tested chyme, tiny aquatic mollusks filled the stomachs of fish even in 45 percentages. In summer and autumn, snails and small mussels in many cases constituted the main mass of the food content of the studied carp.
Occasionally the carp menu also includes other insect larvae, mainly collar bones and flies. Carps also do not disdain dragonfly larvae, food eaten only by a few species of fish. In the stomachs of one third of the examined carps, remnants of grubs were also found. Rosewoods are an important component of the natural carp food, mainly in spring and winter.
However, it was surprising to find cereal grains in the stomachs of carp. Scientists found the presence of corn kernels and other tiny seeds in the stomachs over 90 percentage of fish tested.
Carps are rarely prone to predatory lifestyle.
Quiet feeding fish were found in the stomachs of carp only sporadically, mainly in carps from reservoirs that are poor in natural food, but with a lot of general cargo.

Results of stomach contents tests 1.400 carps from French lakes. The table shows the percentage of fish, where at least traces of the type of food are found in their stomachs. For example u 79 carp, on 100 tested, larvae of bloodworms were found in the digested stomach contents. Scientists only found small fish in the stomachs of a hundred carps.