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Sharks Aquatic vs. Sparks Atmospheric
by Dr Frans J. Cronje on November 20th, 2015

​​Great!!!! We have just received a question from a DAN SA member about a comment in my lecture on Hazardous Marine Life Injuries (HMLI).

By the way, you can click here for HMLI Part 1 and here for HMLI Part 2 on Youtube.

In the section on shark attacks I say something along the lines that "people are 17x more likely to be struck by lightning than bitten by sharks... "

The concern was that the statistic isn't valid since the population at risk of shark attacks are in the ocean, and it is therefore much smaller than those exposed to lightning. 

I was delighted to receive the question! This is fun, and valuable! In fact, we invite you to listen with open but questioning minds! So, please keep the questions coming!

In response: The statistical criticism is partly right and partly wrong: Lightning is not experienced every day, everywhere, and  - even when it occurs - not everyone is outside (exposed) during a thunderstorm. So there is no way of knowing exactly how many people are actually lightning-exposed vs. shark exposed. Also, note that the shark attacks were not limited only to scuba divers, but all who enter the ocean. So, it may actually be a similar number of individuals exposed to either, and some to both.

Therefore, the philosophical basis of the criticism is certainly valid, but the numerical argument is presumptive. In terms of actual data from our own DAN SA data over 20 years: We have had no DAN members bitten by sharks and one DAN member struck by lightning - and survived (I actually took the call!). So, from our data set: the chance of a DAN SA member being bitten by a shark is incalculably small relative to being struck by lightning

Lastly, the statistic given was simply based on global, annual reported numbers for injuries from sharks aquatic vs. sparks atmospheric! 

Hope that helps!

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