An amazing number of eels are bred in the two large ponds in Richmond Park, which is sufficiently evident from the very great quantity of young ones which migrate from those ponds every year. The late respectable head-keeper of that park assured me, that, at nearly the same day in the month of May, vast numbers of young eels, about two inches in length, contrived to get through the pen-stock of the upper pond, and then through the channel which led into the lower pond, from whence they got through another pen-stock into a water-course which led them eventually into the River Thames. They migrated in one connected shoal, and in such prodigious numbers, that no guess could be given as to their probable amount.
The winter retreat of eels is very curious. They not only get deep into the mud, but in Bushy Park, where the mud in the ponds is not very deep, and what there is is of a sandy nature, the eels make their way under the banks of the ponds, and have been found knotted together in a large mass.
Eel-weirs are common in almost all the rivers in Ireland. There are some large ones at, or near Enniskillen, where great quantities of these fish are caught; they are not natives of the lake, but come from the sea when very young, and are intercepted in their return; they never take a bait, nor are ever known to eat any kind of food. Lord Belmore has kept some in boxes for a year, and found this to be the case.
The country people catch them by extending across the water a band of hay, in which the eels get so entangled, as not to be able to disengage themselves, and by these means are easily taken.
There is a very singular eel found in the river Barrow near Carlow. It is like the gillaroo, has a gizzard. This eel is said to be particularly delicious when introduced to table.
The common eel will grow to a large size, sometimes to weigh twenty pounds, but that is extremely rare; in 1799 one was taken out of the Kennet, near Newbury, which weighed fifteen pounds. As to instances brought by Dale and others, of these fish increasing to a superior magnitude, there is much reason to suspect them to have been congers; since the enormous eels they describe, have all been taken at the mouth of the Thames or Medway.