Lightning: Why Does It Kill Humans But Not Our Beloved Fish?

When an angler hits the water, he's looking for action...and lots of it. However, I seriously doubt that any of us is looking for the kind of action portrayed in this photo, which was captured by a GoPro camera back in October 2013.

At the time, 16-year-old Tucker Owings was fishing Lake Athens in Athens, TX.

According to reports, the lightning seen here was so close to his boat, he said it was "like a knock to the back of his head." He had a headache the rest of the day, but neither he, nor his friend, suffered any injuries from their close call. And while they immediately beached the boat and ran for cover after this near-miss occurred, they returned to fishing once the "light show" was over.

One of the youngest professionals in the fishing industry (reportedly turned pro at the age of 14), Owings later would relate, "I just learned a very important lesson and am glad God protected us."

Now, perhaps I'm just an oddball, but as a result of re-reading this Owings story, I began wondering what protects the fish from bolts of lightning. After all, we all hear the warnings about using a hairdryer in the bathtub. So what happens to fish when lightning strikes? Why don't thunderstorms routinely kill off everything in the water?

I found the answer to those questions in a short article written by Ashley Hamer, a science communicator with a wide range of specialties and a deep love of the unknown. As she explained, lightning just doesn't strike the water that much. She cited a 2014 article in the Journal of Geophysical Research, which published a map that amassed five years of global lightning-strike data from two weather satellites. It showed that lightning strikes occur over land 10 times more often than they do over water.

According to the NASA Earth Observatory, this makes sense because of the way lightning forms. Solid earth absorbs sunlight and heats up faster than water does. That heat causes more convection and instability in the atmosphere, which, in turn, causes more lightning-producing storms to form.

Even still, lightning does strike the water sometimes. So why doesn't that kill the fish by the thousands? Physics has the answer. Like metal, water is a good conductor, so it encourages the electrical current to travel over its surface, rather than delve underneath, the same way a Faraday cage protects its contents from harmful shocks. (FYI: A Faraday cage essentially is a container, or shield, that blocks out electromagnetic radiation from across the electromagnetic spectrum, such as radio waves and microwaves. It works on the principle that when an electromagnetic field hits something that can conduct electricity, the charges remain on the exterior of the conductor, rather than traveling inside.)

If a fish surfaces at the wrong moment, it certainly can be hit by lightning. Luckily, though, most fish spend the majority of their time underwater, whereas people don't, and that's why we immediately should get off the water if a storm is approaching.