BULLETIN OF THE UNITED STATES FISH COMMISSION. 91 



30.— EE1.S JN TArVIiS AND PONDS.* 



The fry of eels can easily' be made to grow iu closed tanks, but it is 

 best to lint in some older eels, e. </., some measuring from 8 to 15 inches 

 in length. An eel-tank should be carefully constructed and should be 

 thoroughly tight. Wooden tanks are best, having a lid with a net- work 

 of steel wire, so that the fish cannot escape. At the top they should 

 have a ledge about a couple of feet broad, with fine sand, and outside 

 of that a tight Avail of boards about a yard high. 



The quantity of water iu such a tank should be about C pints to 1 

 pound of large, live fish, but for fish that are a year old about ten 

 times as much water is needed. The' tanks would best be placed in sum-' 

 mer iu fresh running water, or in a lake, so that the waves may have 

 some influence on the inclosed space. In winter it is best to have the 

 tank iu a weak current. 



At the bottom of tanks for small eels stones (about the size of a fist) 

 are placed: and over it a coarse cloth is fastened, so the young fish can 

 hide under it. For larger eels there should be at the bottom flat stones, 

 roots of trees, &c., so they can hide. Eels can be fed in these tanks all 

 the year round, but in September a layer of clean sand should be put 

 on the bottom, so that the eels can hide iu it in winter. 



Eels may be fed on all kinds of animal food, even if it is almost de- 

 cayed, such as dead animals, entrails, refuse of fish. &c. In the tanks 

 it is best, however, to use fresh food, and to take care that no decaying 

 matter accumulates. From the beginning of October till the middle of 

 April the eels do not take any food, because they are in a state of tor- 

 por. But as soon as the eels again begin to take food, they should be 

 fed every other, or at least every third, day at sundown, because the 

 eels generally rest during the day. For young eels the food should be 

 chopped, or it should go through a sausage machine, and be mixed with 

 flour so as to form a dough, then cut iu small pieces or rolled out in 

 worm-like strings. Worms, snails, «Sc;c., also form good food for eels. 

 Larger eels may be given small shells, such as Leuciacus rutilus, &c. 

 When well supplied with food eels will increase in weight from 11- to 2 

 pounds in the course of a summer. 



Ponds are best adapted to young eels. They will grow well in them; 

 and there are instances that about 3,500 young eels, weighing in all 2^ 

 pouuds, which were placed in peat-bogs near Abbeville, France, after 

 five years yielded eels to the weight of G,000 pounds. Any stagnant 

 water, such as peat-bogs, marl-pits, i>uddles, &c., may be used as eel 

 ponds, on account of the many insects, larvoe, and difl"erent aquatic ani- 

 mals found in them. The only condition is, that these ponds should 

 not freeze to the bottom in winter, or dry out in summer. 



* ' Aal i Beholderc og i Damme." From the Xorsic Fiskeruidende, Vol. V, No. 1, Ber- 

 gen, January, l^f6. Translated from the Danish by Herman Jacobsox. 



