THE WONDERFUL LIFE OF THE EEL.

Shannon News, 29 December 1922, Page 4

THE WONDERFUL LIFE OF THE EEL.

Marine zoologists have solved at [ last the ancient' riddle of the. life his- $ tory ol the oSnmiqn eel. Dr. Johs { Schmidt, a Danish zoologist, has now tilled up the last o! the gaps in the tale, and here it is. ..-The adult eels—a male eel is an aUdlt at five or six years of age, and a'female at any-, •thing from five to twenty—from all the rivers,. lakes, and ponds of Europe set nut seawards in autumn .and winter, resting by day and travelling by night, especially on moonless nights. They .probably go about ten miles a night. the open sea they never-return. But, we- know what becomes -of them now. Their place of honeymoon' a&d nursery is a limited tract of : the North Atlantic, about 2500 miles south-west ol England and 500 miles north-east of the Leeward Islads. There the larvae ofthe eel ..are horn in spring and early .summer, apparently between 700 and 1000 feet below the surface. As they grow*-during that first summer they move up towards the surface. Next summer the one-year-old infants are found in the centre of the Atlantic, some impulse urging them north- ■ eastward towards Europe. The summer after they are off the .coasts of Europe. For the ten months following this 'third midsummer of their lives the larvae, now developing irto_ elvers, seem to take no food at adit is a period of some strain, for they have to make their way up the rivers, then up their tributaries, and so—many of them—into remote in : land pools, and at the same time they have to change their gear, as it were from that of sea life to that of the fresh water. However, .the .stout creatures manage somehow to live on their fat. By the following April they are smaller than they were, but they have arrived.

To add an extra marvel to this three-year Odyssey of the baby eel, he comes from a breeding area used, also by a slightly different species, the American eel. The larvae of the two species are found together, and. are sometime taken in the same net. Yet no American larva, as far as is known, makes for Europe and no European larva for America. Dr. Schmidt discovered, why, by following both crowds of larvae up. The American kind, he found, completes its larval stage in one year-just long enough for it to reach the American dOnst before its constitution begins to cry out for fresh water and fresh water things. So if it made for Europe it would, at the end of the first year of the journey, be ca*t- away in mid-Atlantic like a wrecked mariner, with water, water everywhere and not a drop to drink. If.., 011 Ihe other hand, a larva with a European pedigree struck out for America, it

would, have to hang about off thp American coast, like a quarantined ship, for two years until its organism wp-s qualified to go up a river. Either. would perish. One stands amazed and awed at the perfect attitude of instinct which propels each kind of eel, unguided by any accompanying' parent, along the propei route of its own pilgrimage. But amazement grows deeper, if possible, in presence of the apparent- enormity of, Natures exaction o-f effort, both from the emigrant parent's and from* the immigrant young.