the life cycle of an eel
本文同时提供以下语言的翻译:中文
Life of an eel:
I believe that with years of Internet surfing experience, you must have some impression of the transparent characteristics of eel larvae (Leptocephali eel stage) :
For those of you wondering how an eel develops from a transparent larva to an adult, read on.
Most eels are sallow fish (like the Japanese eel) : where they were born, they go to give birth to their next generation.In other words, eels follow a lifetime migration path: they hatch in the sea, develop and enter rivers, then return to the sea to mate and lay eggs, and finally return to peace.
PS: This makes eels from the same region genetically similar.
Generally speaking, the growth and development of eels can be divided into five stages:
(Leptocephali) >(Glass eels)> (Elver) >(Yellow eels)> (Silver eels)
Leptocephali
Newly hatched from an egg, the eel is transparent and only a few millimeters long.Based on their physical characteristics, scholars speculate that they ate organic detritus.Willow eel gets its name because it looks like a willow leaf as it grows taller.This size helps the eel move along currents, or rivers.
In addition, the eel’s body is packed with Glycosaminoglycan, which increases water content and provides buoyancy.
Glass eels
When the eel follows the current into coastal waters, it begins to morph like a tadpole
Development.Within a few weeks, the mucopolysaccharides on the surface of the eel break down, providing the energy needed for the development of bone, muscle and viscera.This is when the body changes from a willow leaf to a cylindrical streamline, the glass eel.
Their motion changes from passive swimming to active swimming.At the same time, eating habits have changed.
Elver and pigmentation
In the glass eel stage, their vertebrae develop quickly.At this point, the subcutaneous pigment begins to develop and form a protective color.
As the color of the eel continues to deepen, it reaches a certain stage and we classify them as eel lines (the boundary between the two is not clear).
Yellow eels
Yellow eels can be considered immature adult eels, and their color varies from black to brownish green to turquoise depending on the local environment.
Yellow eels are also at their fastest growing stage, growing about ten centimeters a year.
Silver eels
The sex of eels is acquired: their gonads do not develop until they are 15-30 cm old.The external factors controlling the sex of eels are still unknown, which may be related to population density, growth rate and water salinity.
Silver eels are the last stage of eel development. Before migrating to the sea, the eel’s eyes become larger, its back and pectoral fins turn black, and its belly turns silver gray to adapt to the deep sea environment.
And then finally I’ll put a picture of all the stages
the life cycle of an eel
