The heat generated from the average lightning bolt (negative charged ) is 5 times hotter than the surface of the sun.( 50,000 degrees F )Positive charged bolts can be 6-10 times hotter and more powerful. So in theory, it is possible to super-heat a small portion of a body of water and lead to the warming of the entire body of water as temps balance. I would think it is plausable that a body of water could be warmed enough to not support certain species of fish quite easily.

I'll start treating my wife as good as my dog when she starts retrieving ducks.
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