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Electric EELS
Eels are freshwater fish found in the waters of South America. They can be found in rivers, lakes and streams, and often muddy swamps and backwaters. They will not venture out to the sea because the salt effectively causes a short circuit during electrical attacks. The electric eel received its common name because of its elongated, snake-­‐like appearance, but it is not a true eel. They are more closely related to carp and catfish. It has been classified and reclassified numerous times, changing as science progresses. Appearance:
The electric eel has an elongated and tube-­‐like body, absent of pelvic or dorsal fins to make them appear more serpentine. They possess a shallow but extended fin that stretches the entire length of the body to the tip of the tail. It waves like an ominous, trailing ribbon as the fish swims. Their bodies are generally grayish brown on the upper side & yellowish on the underbelly, with mature males becoming a darker orange underneath. It has no scales, but features a thick slimy skin, which protects them from harm, including its own electrical current. Electric eels can become quite large, some growing over eight feet. They are very muscular & can weigh fifty pounds when mature. They are a top predator & have no natural enemies. Using Electricity:
The electric eel is a very effective predator, despite its poor vision. It has an excellent sense of hearing, and also a Sachs organ, which has been linked to electrolocation. This organ emits a low voltage charge of about 10 V. It is thought that the eel uses these weak charges for orientation, as well as locating prey and potential mates. Some scientists feel it is also used as a form of communication. The more powerful electrical charges come from the Hunters Organ and the Main Organ. When the eel becomes upset or is preparing to attack a prey animal, its brain signals the electric cells in these organs. An ion channel is opened and positively charged sodium flows into the organs, reversing the charge for a moment. The product of this sudden shift or disturbance in voltage creates an electric current. Eels can produce a shock typically as powerful as 650 V but have been known to emit bursts over 700 V. These are the shocks issued during predation and defense. In total, the three electric organs make up 80% of the electric animal's body, with the vital organs comprising the other 20%. Eels prey upon a range of smaller creatures. Eels have the luxury of taking their time while consuming a stunned animal. They prey upon mammals and fish, & sometimes inveterbrates if an easy opportunity presents itself. The younglings will eat invertebrates, primarily crabs and freshwater shrimp. Newly hatched eels will also consume the eggs and embryos from later batches. As many as 17,000 eggs can be laid in a nest made of a male’s saliva. Eels and People:
Deaths to people from electric eel shocks are very rare. Repeated shocks can cause respiratory & heart failure. People drowning after being stunned is more common. The eel is a coveted pet in some areas, but are difficult to catch. However, releasing repeated charges will wear out an eel, making them vulnerable to capture. In captivity, an eel must be kept in a tank no smaller than 100 gallons and should be the sole inhabitant of its artificial environment. Adult eels will generally tolerate one another, but young eels will fight for supremacy and eels of any age will attack other fish. Occasionally, eels are also used as a food source. Their ability to emit a powerful charge up to eight hours following death helps prevent this, though!