What the Christmas Eve carp won't tell you...

Carp prepared in various forms is one of the most popular dishes on Christmas Eve in Poland. Every year, approximately 21,000 tons of carp are sold in our country , 90% of which - in December ¹ . Poland is also among the European leaders when it comes to breeding these fish (together with the Czech Republic and Hungary). ² . Most carp producers are family farms that have been running ponds for many generations. Organizations associating native fishermen argue that carp is a natural product and not only does not disturb the ecology, but even supports the biological diversity of species . Are these fish farms really ecological? Is buying live carp ethical? Is eating carp healthy? Read on to find out the answers to these questions.

How are carp bred?

Carp is a freshwater fish . It is an undemanding species and can be grown even in shallow and muddy ponds , it is able to adapt to various conditions. In terms of food type, it is basically omnivorous . It eats invertebrates, larvae, worms, mollusks, leeches and other small aquatic organisms from the bottom, as well as plants and algae. In breeding ponds, carps are fed with grain feed , to which fishmeal and oil are added in spring ³ , but sometimes also meat meal, frogs or soy ⁴ . After 3 years of breeding, the carp is moved to special "warehouses". These are water reservoirs about 2 meters high, in which there are neither plants nor food. The carp eat nothing for 2 months , waiting to be sold . However, before this happens, they must also go through a "washer" in flowing water, which helps to get rid of the "silty" taste ⁵ .

Not all producers focus on slow-growing carp . As it is an undemanding species when it comes to food, it can also be bred using high-energy pellets . They make the carp grow faster, but also have more fat and a bitter taste ⁶ . Even if carp are fed with grain, fishmeal and oil, the question arises about the quality of these raw materials . Especially considering the recent scandal involving chickens that were fed with feed containing technical oils... The food that carp eats directly determines the content of ingredients in its meat and fat. ⁷ .

Not all producers take care of sufficient space in ponds - sometimes fish are bred in great densities. In theory, of course, carp breeding conditions should be similar to those existing in wild nature . In practice, however, it varies.

How do carp farming affect the environment?

One of the most frequently raised arguments for the development and support of Polish carp production is ecology. Due to the fact that the ponds in which these fish are bred are not deep, the steam from the water does not rise high, but increases the humidity of the surrounding areas. This creates conditions for lush growth of plants around the ponds. Plants, in turn, attract birds and animals. You can often see white-tailed eagles, cranes, swans, herons, storks, hoopoes and owls in the vicinity of such water reservoirs, said Dr. Mirosław Kuczyński in an interview for Wirtualna Polska ⁸ . Carp ponds also increase the amount of water resources in the country ⁹ . If consumers stop eating carp, producers will not take care of these reservoirs - the ponds will overgrow and entire ecosystems built around them will be at risk. ¹⁰ .

On the other hand, carp is considered an invasive species , also in Europe ¹¹ . This means that an excessive increase in the carp population may lead to the extinction of other species of wild fish, which reduces biological diversity in the aquatic environment.

It is worth remembering that carps are often used to "stock" lakes . As it is a fish that looks for food deep in the mud , it also picks up chemical compounds lying at the bottom, including: phosphorus or other chemicals that, unfortunately, are present in Polish water reservoirs, which anyway combine into one common system. Only 10% of Polish rivers are in good or very good ecological condition ¹² . The chemical condition of lakes in almost 70% of reservoirs is below good ¹³ , and their waters are in poor condition in 88% of cases ¹⁴ . Lifting toxic compounds from the bottom of lakes certainly does not benefit the biodiversity of this environment. The question is also - do these chemicals not settle in the bodies of the carps themselves?

Selling live carp – is it ethical?

December sales stands for live carp are seen less and less frequently (although they still exist). Some supermarket chains have abandoned this form of sales . One of the reasons for this is undoubtedly high-profile social campaigns , including: Gaja Club's campaign "Still alive carp" ¹⁵ with the participation of famous Polish actors. Non-governmental organizations have long been warning about the fact that carp are living creatures that, like other invertebrate animals, feel pain. ^16,17 . What's more, carp can even distinguish music genres ¹⁸ . They hear and feel what is happening around them.

The transport of live fish to the place of sale, the conditions of sale and the way in which they reach consumers' homes (usually in plastic nets without access to water and air) cause carp to suffer . For this reason, among others WWF Poland Foundation in its official position ¹⁹ spoke out against selling and buying live carp :

“Keeping fish crowded together in a small amount of water, and even more so transporting them without water and killing them in shops or markets, is intentionally causing suffering to these animals , inhumane behavior and violating the Animal Protection Act. Transporting live fish from the store to your home, even if they are in the water, is still exposing them to unnecessary fear and stress . Transporting strictly aquatic animals without water is intentionally torturing them . Moreover, it is impossible for a consumer buying a live carp, who is not specially trained and lacks the appropriate tools, to be able to kill the fish without causing it additional stress and suffering.

Non-governmental organizations encourage consumers to document cases of mistreatment of carp during the Christmas period and share them online. Sellers may be fined (up to imprisonment) for failing to provide appropriate conditions for live fish - the law treats this as animal abuse. ²⁰ . Even the Supreme Court issued a judgment regarding the defense of carp in 2016 ²¹ .

In response to the controversy regarding the sale of live carp, breeders emphasize that the sale of ready-made, processed fish carcasses - chilled or frozen - does not pose any problem for them. ²² . We will never know exactly how these fish will be killed and whether they will be tortured (in accordance with the Animal Protection Act).

Is eating carp good for your health?

Carp meat is often praised for its protein content (about 18% of the composition) ²³ . This type of fish is considered medium-fat - it contains 2-5% fat (for comparison, salmon has about 7% fat). Carp meat is a source of Omega-3 (EPA and DHA) ²⁴ , however, this type of acids constitutes only a few percent of the total amount of fats it contains ²⁵ . The rest is mainly Omega-6 fats , which we modern humans consume too much of anyway . When it comes to these types of acids, the ratio of Omega-6 to Omega-3 is the most important. A diet rich in Omega-6 acids (with low consumption of Omega-3 acids) is associated with an increase in the number of chronic inflammatory diseases (e.g. non-alcoholic fatty liver disease), cardiovascular diseases, obesity, inflammatory bowel disease, rheumatoid arthritis and Alzheimer's disease ²⁶ . In other words, Omega-3 fatty acids from carp are unlikely to allow us to benefit from their benefits (read more about them in this article ), because we will not be able to eat them separately from Omega-6, which is much more abundant in carp meat.

As for other nutrients, carp, like other fish, also contains iron, zinc, calcium, collagen and vitamins B and D. ²⁷ . However, let us remember that on Poles' Christmas Eve tables, carp is most often fried (in flour or breadcrumbs). Thermal treatment reduces the content of valuable ingredients , and frying itself causes the formation of compounds toxic to the body .

To eat or not to eat carp on Christmas Eve - an individual matter. However, when making a decision, it is worth being aware of its ecological, ethical and health consequences .

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