Re: How does an electric ray deliver his shock?

G'day Kamel,

Electric rays are facinating animals - in Australia we have quite a few 
different species, and they don't all look identical.

Electic rays have special kidney shaped organs which are located on the 
main "disc" of the animal, just behind the eyes.

In these organs, there are little hexagonal cells, which are filled with a 
jelly (jello?) like substance connected to their very complex nervous 
system.

Now these cells work like a battery. They can charge up, much like the 
flash in a camera, and use the upper surface of the fish as the positive 
part of the battery, and the underneath as the negative side of the 
battery.

So if the ray was flapping about on a wet ship deck, and a fisherman 
touched the top half - they get a big shock! There's been reports of 
people being thrown a meter or two after inadvertedly touching an electric 
ray. One family of electric rays (Coffin rays) are so efficient at 
electricity production, you can get a nasty (but not fatal) shock from 
just pouring water over the animal.

Bringing the whole thing back to the ecology of the animal; electric rays 
use their special talents to stun prey - most of them eat crabs, benthic 
worms and slow moving, bottom dwelling fish.

The crux of the whole thing is, if you're helping someone sort a catch on 
a trawler, stay away from rays! Even if it's not an electric one, it will 
still have a nasty spine on the tail that will cause a dreadful infection 
if it catches your skin.