European eel is one of the most extraordinary fish that can only be found on our planet. Over their entire lives, they undergo such a number of amazing metamorphoses and overcome such distances that their exploits are astounding. You can start with the fact that eels are fish that live in fresh water, but breed in the ocean.
From all over the world they sail for the sargasso sea. Only the hatching larvae are attributed by the powerful ocean current to the shores of Europe. A long and incredibly dangerous journey lasts as long as three years.
Only off the coast of Eurasia, eels finally reach seven to eight centimeters in length, but the difficult road does not end there. Whatever you say, but eels are fish that are very stubborn and consistent in their aspirations.
Having reached the rivers, they gradually climb along them to the places where their parents lived. Here they live up to 25 years, and then repeat the path of their ancestors to the Sargasso Sea. To overcome this whole difficult and treacherous path, they are often forced to creep between rivers up to a dozen kilometers!
And all this - for the sake of a seven thousand kilometers road and spawning, after which death awaits them … In a word, eels are fish that are very similar in this regard to salmon, but their migration is the opposite.
By the way, their tender and very tasty meat has been valued since ancient times. Even at the feasts of the great Alexander of Macedon, it was served to the most honored guests. Even then, one question was haunting scientists: “How do these fish reproduce if none of them ever found caviar or milk”?
Then Aristotle suggested that eels are fish that originate in coastal silt!
Surprisingly, this thought of the great thinker has been dogma for … two millennia. And only in 1694 did the great Italian naturalist and natural scientist Francesco Redi put forward the correct assumption.
He spent several years watching eels. Redi followed them and found out that these amazing creatures are gathering in flocks and floating down the rivers, heading for the seas. Indeed: all eel fish (where a large number of them are found) sometimes disappeared from some places, but no one paid any attention to these fluctuations in numbers.
Of course, few believed him. After all, the naturalist did not provide any convincing evidence!
An indirect confirmation of the bold hypothesis was the experience of Cazzi, another Italian scientist and nobleman. Almost 200 years after the Redi theory, he caught an extremely unusual fish in the Gulf of Messina, which no one had previously described.
The “new species” was called leptocephalus. In 1897, a couple of these fish were placed in an aquarium and began to observe. A year later, a startling discovery awaited them: the bodies of leptocephalous were shortened by a centimeter, lost their specific leaf-shaped form, turning into ordinary eels!
However, not only freshwater species exist. In particular, the fish eel marine European. It grows to a length of three meters and can reach a weight of 120 kilograms!
By the way, the reproduction of this species has not yet been precisely studied. It is known that for spawning eels descend to great depths. The breeding area is Gibraltar. But there are no details about the exact place for spawning, and the process itself has not yet been described by anyone.
