(CN) - A researcher is stunned by the ways the Amazon's electric eel uses its voltage, doubling it when needed and repeating the jolts 20 times faster than a Taser can, the National Science Foundation reported.
In his latest study, published in the journal Current Biology Wednesday, Vanderbilt University's Stevenson Professor of Biological Sciences Kenneth Catania reported the electric eel can dramatically increase its electrical field by curling around itself to stun larger prey.
In a typical attack, the eel uses pulses to stun small fish and eat them before they recover and swim off, Catania said.
For larger prey, such as a large crayfish, the eel first bites the prey, and then curls itself into a circle with the prey between its head and tail, he said.
The head gives off a positive charge and the tail a negative one, Catania found. With the prey in between, the eel more than doubles the voltage, which can take it beyond 600 volts, or five times the voltage of a standard U.S. wall socket, he said. The eel also increases the rate of pulses for large prey.
Shocking the prey causes nerves to fire, which move the prey's muscles to the point of exhaustion -- just how a Taser works, Catania reported after an earlier study.
"A Taser delivers 19 high-voltage pulses per second while the electric eel produces 400 pulses per second," Catania told Vanderbilt's science reporter in 2014.
The professor had also found another way the eel hunts in the muddy Amazon or Orinoco River, where it lives.
Here, the eel swims through the water giving off pairs of high-voltage pulses, or what Catania calls "doublets."
"That is the perfect stimulus to cause a massive full-body twitch. And that twitch is the cue to give away the position of the prey to the eel, which is very sensitive to slight water movements, so it'll attack a very slight water movement," he said in a video for a 2014 study.
Eels also use high-voltage pulses as a sophisticated radar system to locate fast-moving prey just before a strike, similar to a bat's use of sound during hunting, Catania wrote in the online Nature Communications journal Oct. 20.
An electric eel, which is actually not an eel, but a long carp, can weigh more than 44 pounds in lengths over eight feet, and can bring down a horse.
Catania's study was funded in part by the National Science Foundation, an independent federal agency, which featured the research on its website as "News From the Field."
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