European eel fish farming is gradually spreading all over the world. At a time it was only farmed in European countries but with help of modern cultivation, this breed is farmed in Asia and in many African countries commercially.
It is a catadromous, carnivorous, and freshwater species. There are several types of eel-like freshwater eels, saltwater eels, electric eels, true eels, Japanese eels, American eels, etc. Generally, the young European eel lives in freshwater. Normally the male and female eels stay in freshwater for a period of 6-12 years and 9-18 years respectively. Because the eels become sexually mature they migrate to the ocean, where they move to the spawning grounds within the Sargasso Sea. During migration, the eels don’t feed.
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Nature of European Eel
The main feature of European eel is they are well known as strong swimmers, though they need outstanding climbing skills, too, allowing them to navigate obstacles like dams in their upstream journeys. There are even descriptions of European eels allowing for the water altogether and entering fields, where the species banquets on slugs and worms.
Once within the Sargasso Sea, the eels spawn in late winter and spring. Adult eels don’t leave the Sargasso Sea but their progeny, the leaf-shaped larvae (leptocephali) are delivered to the ocean floor of Europe by the Gulf Stream, a journey that takes 200-300 days.
Life Cycle of European Eel
European eels undergo several easily recognizable life stages on their journey to adulthood. As larvae, eels are referred to as leptocephalus due to their thin heads and wider bodies that give them a leaf-like shape, but as they age, the animals become longer and thinner. As their bodies become larger and more translucent, the fish become referred to as “glass eels.”
Next, because the eels enter freshwater systems, they transform again, gaining pigmentation and becoming referred to as “elvers.” For subsequent six to twenty years, the eels placed on weight and length while also developing lemon-colored undersides. This is often what’s referred to as the “yellow eel” stage.
Yellow eels move ceaselessly upstream towards the cooler place, and less salty water until they become adult or generative mature. Finally, the fish transform again into “silver eels” with a metallic sheen and enormous eyes, at which point they migrate thousands of miles back bent the Sargasso Sea, where the animals spawn, lay eggs, and die. Much of the European eel’s life cycle while out stumped remains a mystery story.
Habitat and Diet
This species is not only nocturnal but also secretive, and preferring to burrow into the mud and under stones during the day. At night, European eels emerge to prey on a spread of food sources, counting on their life stage. Their diet includes everything from other fish to shellfish and arthropods, to even insects, worms, and carrion.
This eel was firstly considered to be American and European eels were the same because it resembles similar behavior and appearance. But it varies within the chromosome count, various genes, and vertebrae numbers. The spawning of yank eel occurs in Yucatan. After it breeds in the Sargasso Sea it moves towards the west. American mainly eels exits in Gulf Stream, and most early in European eel and migrates in estuaries ahead East Coast of North America in between February and late April.
Nutritional Value
Eel is one among the fishes that are present almost everywhere in rivers, canals, lakes, and other freshwater reserver. Apart from its testy and distinguishable flavor, it offers various health benefits. Eel fish helps to lower cholesterol, vital sign, and chances of arthritis. It enhances the event of the brain, good eyesight, and functions of the nervous system. Eel’s fish is good for us as they contain Omega-6 fatty acids, and then have all the advantages of other oily fish like mackerel and salmon.
They contain the minerals calcium, magnesium, phosphorous, potassium, sodium, selenium, manganese, zinc, and iron. As for minerals, they’re a really good source of vitamins A and B12 and also a really good source of protein. They contain no carbohydrates but have 18 amino acids and vitamins A, C, E, K, the B-complex vitamins, B1, B2, B3, B6, folate, B5, B12, and choline. This suggests that they’re heart-healthy, protect the central nervous system, help vision, promote hair growth, and help rejuvenate the skin, and in fact, there’s selenium, good for the brain and a mood enhancer.
European Eel Fish farming:
To run a commercial European eel fish farming you need to learn several things. Like carp fish farming and tilapia fish farming, there are some rules that you have to follow.
Farming of eels is proclaimed on wild catches of glass eels or elvers used for further growth. Encompassing European eel fish farming under the usual situation has diminished to a level of no commercial importance. Intensive production by the utilization of recirculation technology, keeping water temperatures stable around 24 °C, has become the general production method.
1. Business Plan
First of all, you need a perfect business plan for European eel fish farming. As we know that at present everything highly depends on a well-defined business plan. A perfect business plan must include the business model, business operation, and financial projection properly. So before starting a European eel fish farming business you must ready it.
2. Site selection & Pond Selection
Site selection is another crucial matter in the case of European eel fish farming. Though it is farmed in the special pond today it is farmed commercially in an artificial pond artificial way, it is farmed in various types of ponds such as an earthen pond, tank, concrete pond, cage, and even brackish waters in the river or using Biofloc system. As a commercial fish farming method, you have to find out a suitable place for successful European eel fish farming.
The traditional sort of eel culture in Europe is in ponds of about 100-350 m². When eels reach the marketable size they’re transferred to larger ponds (1000- 1500 m²). The ponds could also be static or flow-through. The simplest temperature home in ponds is 18-25 °C.
Here we describe two differences types of farming method in short
(a) Intensive Culture In Recirculation Systems
These systems contain square or circular tanks from 25-100 m², usually built of cement or fiberglass. The eels are stocked at a size of fifty g. Densities reach up to 100-150 kg/m². Extruded dry feed (1.5-3 mm) is fed automatically several times each day. Individual growth rates are very different, and grading every 6 weeks is important so as to succeed in high overall growth performance.
(b) Valliculture
European Eels also are extensively farmed in marine and brackish waters within a sort of aquaculture mentioned as valliculture. In these Mediterranean systems are practiced mainly in Italy, within the north Adriatic, elvers of 15-35 g are stocked at the speed of 4-15 kg/ha. The elvers are mainly imported from France but sometimes imported from Denmark, Netherlands, and Sweden.
3. Seed Supply
Glass eels are collected from the shores of France, Portugal, Spain, and therefore the UK and either used nationally or exported to eel farmers in other countries. For commercial European eel fish farming, you can collect artificial hatched seeds from your nearby hatchery. Spain and Portugal use scoop nets and traps to capture glass eel, where in France they’re caught by small trawlers using wing nets and trawls France. The sole legal tackle for this purpose within the UK is that the scoop net.
4. Nursery
At first, up to 0.33 g body weight glass eels are kept in comparatively smaller tanks of 3-4 sqm. for quarantine purposes. The denseness at this age is upto10-15 kg/m². The eels are examined carefully for diseases and, following diagnosis, treated. The eel fishes also are ablactated to artificial diets with cod roe and, later on, dry starter feed.
In commercial European eel fish farming when the eels reach about 5 g they’re shifted to a juvenile production unit with comparative larger tanks (6-8 m²) and stocking densities (50-75 kg/m²). At now the eels can digest dry feed pellets (1 mm). On growing techniques
5. Feed Supply
European eel fish farming commercially is not easy. Proper feed supply and nutrition must be supplied timely on the farm. Almost all sorts of intensive farms generally use formulated feeds within the sort of a moist paste for glass eels and steam-pressed or extruded pellets for the later stages. At present many commercial feed manufacturer produces eel feed in many countries though, several European aquafeed manufacturers produce eel feeds.
6. Diseases Control
For commercial European eel fish farming disease controlling is very much necessary. European eels are vulnerable to numerous parasites, fungi, bacteria, and viruses which will cause disease outbreaks. However, in aquaculture, only a couple of disease agents end in disease outbreaks that decrease growth or increase mortality. Commonly seen disease agents are listed within the following table.
7. Monitoring
The success of commercial European eel fish farming mainly depends on proper monitoring. Proper monitoring comprises of measurement of water quality ( water treatment), an inspection of the health of the eel, presence of food in the farm, weight monitoring, etc.
7. Harvesting
Proper harvesting and grading are important facets of successful European eel fish farming. The particular technique used is straightforward but care is important to minimize stress. Providing feeding is suspended a minimum of 1-2 days before grading or harvesting.
Eels are led to passive immunity through a pipe from the farming tank to a grading machine to find out the actual size. Eels large enough for the market are addressed as indicated within the following section of this fact sheet. Eels that haven’t reached market size are returned to the rearing tanks for further growing. During harvesting, care is taken to stay oxygen levels high.
8. Marketing
After harvesting, eels are rapidly sorted into different sizes, in different grading systems. They’re kept in normally holding tanks without any feed for several days to purge their stomachs and eliminate possible off-tastes. If they are to be consumed fresh, they’re chilled, packed into strong oxygenated plastic bags with only enough water to make sure that the skin remains moist, and transported to plug.
If they’re destined for processing they’re transported live to the processing plant. Most Danish cultured eels are smoked at shamrock processing plants, while a smaller part is skinned in Denmark for frying.
9. Keep A Note
After harvesting and marketing, you need to find out profit or loss. If there is profit then you can consider it as a good business plan and your business operation is right as well as your financial projection. But if there is loss then think something wrong, what is wrong try to find out. So if you have a note then you will get any information from it easily.
Where the European eels are found?
European eels are often found from the northern reaches of Russia and Finland all the way right down to the coasts of Morocco, Egypt, and even within the Black Sea.
