When talking about wonders of God and his made creation, eels also comes in list. What are eels? Where do eels come from? A lot of scientists are researching over this specie. And trying to find and combine their answers.
Eels are basically a form of fish from the order Anguilliform. They have a worm like body. This fish is different from electric eels. Electric eels are not real eels; they are basically South American knife fishes.
Eels are often found in depths of most oceans and are greatly diverse in tropical seas. Their range of color varies from dab gray to dark black in deep seas whereas colorful and patterned in tropical reef species. The fresh water eels are in places abundantly and greatly valued as a food product and are of major economic importance.
WHERE DO EELS COME FROM
This question has troubled minds of scientists from time immemorial. Every philosopher presented its own theory towards the mystery of eel’s origin.
A famous scientist Aristotle suggested that eels came from Earthworm that comes out of mud whereas other scientists claim that the come from spontaneous regeneration.
NATURAL HISTORY OF EELS
Study shows that have remarkable life cycle. Their development and early growth takes place in Open Ocean. Eels are not great swimmers in their beginning phase of life; eventually the current of ocean carries them from one place to another. Eel’s body goes through various changes at each occurring stage of life. Gradually b time they get more prominent feature because of their darker skin.
EELS HAVE REPRODUCTIVE ORGANS OR NOT
Regarding this question a zoologist presented a theory in which she states that form from external fertilization, moreover, she stated that cloud of sperm fertilize free floating eggs.
Scientists curiosity led to another level fantastic discovery that was spawning’s travel by ocean currents from the Sargasso Sea.
LIVE STAGES OE EELS
Eels comprises of two sexes. The life spans of young males are average of 12 years while average of females live longer at 18 years. Eels go through five live stages,
- Glass Eel
- Silver Eel
In this stage, eel egg transforms into eel larva, it is also called as fingerlings. They got bigger bodies comparatively to other fish larvae. Larva usually absorbs yolks and teeth and later they feed on snow marines. It takes 17 months to larva travel towards estuaries.
At 18 month it is formed into underdeveloped form of glass eel. Later on juveniles enter the river bay.
At 2 to 3 years elvers starts to form. They are identified by dark yellow pigment on them. Their size resides between 8 to 20 cm. Elvers prey upon worms and insects for their nourishment and growth. After 10 to 14 years until they get mature then they travel back to Sargasso Sea.
The final stage in the life cycle of eel is Adult eel also called as Silver eel. Their size varies from 60 to 80 cm in salt water. Silver eel eventually develops a silver skin tone as sign of their maturity and then they move to tropical sea. The female adult eels release eggs for male fertilization after which they both die. The cycle hence continues.
FARMING OF EEL
Eel farming holds an important role in aquaculture industries worth billions dollar. According to a statistics 60% of people consume eel meat; this is because eel is a nutritious source of protein. This venture usually takes place in Europe, Morocco, Australia, Taiwan, China and Scandinavian countries. Japan is said to be the largest single producer.
Eel farming is proving to be an endangerment to some species. Research shows that yellow pigmented eels and silver eels are at high risk of extinction whereas the American as well as the European eels is on various endangered species list. This is one of the rising reasons that the ban on eel trade has been made.
EELS REPRODUCTION IN CAPTIVITY
As far as we know breeders buy elvers to restock depleting ponds. Experts’ advice owners state that it is essential to quarantine new stock to prevent infections. However, majority agrees to the partial fact that do not have reproductive organ whereas some disagree to it.
Recent discoveries back up this certain claim of existing reproductive organs in adult when they reach the Sargasso Sea. The reason behind why this specific patter takes place is still a mystery.
SPECIES OF EEL
Research shows that there are many variations of Anguilla species, each one consist of different breeding grounds. The eel that grows on brackish water and fresh water are the most popular. American and European eels look similar unless you note variation by a closer look. Their internal organs are different. Others include American eel (Anguilla Rostrata), Japanese eel (Anguilla Japonica), South African eel living on the ocean off Madagascar and New Zealand long fins.
INFORMATION ABOUT AMERICAN EELS
This specie said to be lying in the middle of the conservation scale. When it comes to its life span they mostly spend it in fresh water and the Baltic Sea. According to recent studies, it is stated that the American eels tends to migrate across the continental shelf to the Sargasso Sea in the early spring for the purpose of spawning.
With the help of satellite implants, scientists tracked the movement of mature one. This specie is as prevalent as its European counterpart.
It is a vast theory of where do eels come from? Even if the hypotheses on the eel breeding places are dependent on speculations, they are not unreasonable. Eels move from Sargasso Sea to open seas and eventually return there, which is a fact.
Scientists may never be capable of verifying this since mature one are unlikely to be trapped in estuaries and up streams. Perhaps, in the near future, scientists will develop the fortitude, to command even riskier expedition into the Sargasso Sea.