Why does fish not get shocked during thunderstorms even though water is a conductor of electricity?
Yes, it does. Because water conducts electricity, when lightning strikes water it spreads out along the surface. Any fish near the surface of the water get electrocuted. I’d suggest you check out a 1941 article in Copeia (a scientific journal about fishes, amphibians, and reptiles) called “Mortality at Fish Hatchery Caused by Lightning,” but really the title pretty much says it all. A 2005 episode of NOVA documents an instance of fish in a koi pond being injured by lightning; my guess would be that fish electrocution by lightning is a pretty underreported phenomenon.
