"Marine biologists said the chances of being attacked by a shark are 1 in 11.5 million.
Last year, there were 23 shark bites in Florida, according to the University of Florida."
Can someone help me reconcile these two factoids? What does the 11.5 million refer to? Times a person goes in the water? Number of people in the world? I doubt that 264 Million people went swimming in Florida last year.
For me, the relevant “odds” would relate to people actually going in the ocean, but the 1 in 11.5 million doesn’t seem to relate to that at all.
The article doesn’t say which marine biologists or where the calculation comes from, so we don’t know how the two factoids can be reconciled - there just isn’t enough information.
A reasonable way to do this would be to calculate the likelihood of shark attack per human-hour in the water, but you can guess that would be a difficult task - how would you know how much time everyone spends in the water?
Your best bet is to visit the International Shark Attack File, which attempts to keep records on this sort of thing and put it into perspective. Absent information on how much time people spend in water, comparison to other rates of death or injury seem to be the best measure of shark attack risk.
I recently heard that since accurate records of shark attacks have been recorded (late 1800s?) that there have been less then 100 fatalities…looking for source…
Thanks, that site is helpful.
Their number is based on “attendance”, which I presume means a visit to the beach and/or swimming, which is not totally irrelevant, I suppose. They get an attendance number of 264 million, with 23 shark attacks, giving the 1 in 11 million number. The “attendance” number is way higher than I thought it would be, and is close to the total population of the USA, which is why I thought they were giving us a somewhat pointless “attacks per population of the USA”. Although, it seems that every single attack was in Florida, and I’d bet the “attendance” number is a nationwide figure. So, I’d be curious to know what the odds are for Florida alone. Seems like a pretty sharky place!
There are 17 million or so people in Florida, iirc. I am one of them. We go to the beach many times a year, less than some, more than others. Most tourists go to the beach (and theoretically also dip their toes, at least, into the water while they are here).
I’d suggest that the 264 million attendance is based on Florida alone, although I couldn’t say if that’s visits to the beach or hours spent in the water. I’d guess that most shark incidents occur with people indulging in more dangerous behaviour, like swimming at dusk, near schooling fish, or deeper* water as a solitary swimmer.
*Deeper than ankle deep, but probably less than 50 feet deep. It’s my understanding that most shark attacks occur in relatively shallow water.
The page I linked to states that the 264 million estimated attendance is from both west and east coast US lifeguard agencies. I imagine that’s individuals attending (probably not repeated - although it doesn’t state that explicitly.)