Carole Starr, age 13, of South Portland, Me., for her question:
WHERE DO ELECTRIC EELS GET ELECTRICITY?
Eels are often caught by fishermen as the fish migrate downstream to lay eggs in the sea. The fishermen use nets or set line, and sometimes small wire traps called eelpots. Anglers fishing for eels call the sport "bobbing for eels." For bait they string worms on a thread. The eels cling to the bait with their sharp teeth and are caught before they will let go.
An eel is a fish that looks like a snake. Most of them live in oceans but many of them spend most of their lives in fresh water.
An electric eel is a fish that is related to both the catfish and the carp that can give a strong electric shock. It is not a true eel, but its long, snaky body makes it look very much like one.
The electric eel can be found in the shallow, muddy waters of the Amazon and Orinoco rivers of South America. It has a flat head and its eyes are close to its mouth. But inside, the electric eel is quite different from an eel.
Most of an electric eel's organs lie in the front fifth of its body. The other four fifths mainly hold the organs that make the electric current. The tissue in this part of the body is made up of many layers, one behind another much like the plates in a battery. The current they produce flows from the head to the tail.
Experts in the field tell us that certain swimming muscles in the electric eel's ancestors probably changed into the electric organs.
Electric eels have three pairs of electric organs. The largest pair runs almost to the tip of the tail. Under these are located two smaller pairs.
The electric shock is used by the fish to catch food and to protect itself from enemies. It can detect objects at a distance under water by electricity. Weak shocks from the smaller organs serve as a telegraph to other electric eels. The electricity usually damages the fish's eyes and this telegraph system may take the place of eyesight.
When excited, the electric eel produces strong shocks in sets of three to five. Each impulse lasts only a fraction of a second but the eel can keep them up for long periods of time, perhaps hours.
An electric eel can reach about 200 or 300 volts. This amount of electricity is enough to stun a man or a horse. It is also enough electricity to light a neon lamp. Unusual eels have been known to discharge 500 to 800 volts.
An electric eel's weak shocks also serve as a warning signal to enemies.