ELECTRIC EELS

The most important fact to know about an electric eel is that it is not an eel. Although it has an elongated body like an eel, the electric eel (Electrophorus electricus) is actually a type of knifefish. 
 The electric eel was first described by Linnaeus in 1766 and since then, has been reclassified several times. At present, the electric eel is the only species in its genus. It is only found in muddy, shallow waters surrounding the Amazon and Orinoco rivers in South America. 
 Electric eels have cylindrical bodies, up to 2 meters (about 8 feet) in length. An adult may weigh 20 kilograms (44 pounds), with males being much smaller than females. They come in a range of colors, including purple, gray, blue, black, or white. The fish lack scales and have poor

While the fish live in water and possess gills, they breathe air. An electric eel needs to rise to the surface and inhale about once every ten minutes.
Electric eels are solitary creatures. When they mass together, the group of eels is called a swarm. Eels mate during the dry season. The female lays her eggs in a nest the male constructs from his saliva.
 The fry eat unhatched eggs and smaller eels. Juvenile fish eat small invertebrates, including crabs and shrimp. Adults are carnivores that eat other fish, small mammals, birds, and amphibians. They use electric discharges both to stun prey and as a means of defense.
 In the wild, electric eels live about 15 years. In captivity, they may live 22 years. 
 An electric eel has three organs in its abdomen that produce electricity. Together, the organs make up four-fifths of an eel's body, allowing it to deliver low voltage or high voltage or use electricity for electrolocation.

The Main organ and Hunter's organ consist of about 5000 to 6000 specialized cells called electrocytes or electroplaques that act like tiny batteries, all discharging at once. When an eel senses prey, a nervous impulse from the brain signals the electrocytes, causing them to open ion channels. When the channels are open, sodium ions flow through, reversing the polarity of the cells and producing an electric current in much the same way a battery works. Each electrocyte only generates 0.15 V, but in concert, the cells can produce a shock up to 1 ampere of current and 860 watts for two milliseconds. The eel can vary the intensity of the discharge, curl up to concentrate the charge, and repeat the discharge intermittently for at least an hour without tiring. Eels have been known to jump out of the water to shock prey or dissuade threats in the air
 The Sachs's organ is used for electrolocation. The organ contains muscle-like cells that can transmit a signal at 10 V of about 25 Hz frequency. Patches on the eel's body contain high frequency-sensitive receptors, which give the animal the ability to sense electromagnetic fields. 

Electric eels can be dangerous

 

A shock from an electric eel is like the brief, numbing jolt from a stun gun. Normally, the shock can't kill a person. However, the eels can cause heart failure or respiratory failure from multiple shocks or in persons with underlying heart disease. More often, deaths from electric eels shocks occur when the jolt knocks a person in the water and they drown.
Eel bodies are insulated, so they don't normally shock themselves. However, if an eel is injured, the wound can make the eel susceptible to electricity. 
ELECTRIC  EELS