The researchers used data collected between 1960 and 2015 in the International Shark Attack File of the Florida Museum of Natural History for a global statistical analysis of shark attacks.
The study was published Wednesday in the journal PLOS ONE.
"I was curious to know the probability of shark attacks in a number of years in different parts of the world," said Stephen Midway, lead author of the study and assistant professor. at the Department of Oceanography and Science Coast of the University of Louisiana State, in a statement. "While shark attacks are often reported in numbers, we have taken into account the regional human populations to determine the rate of shark attacks in the world.I think this information could contribute to a more scientific discussion about sharks in general and contribute to their management and conservation. "
The researchers found that shark attack rates are low, but they have doubled in heavily populated areas such as the east coast of the United States and southern Australia, the attacks having doubled at over the past 20 years. But depending on the population of these countries, the rate could be as low as one attack per million inhabitants.
"As development grows along the coast and beach communities, more and more residents and tourists frequent these waters," Midway said. "With more people in the water, the chances of shark attack are increasing.However, I must point out the fact that not all places around the world have experienced an increase. in places where we saw an increase, the odds were still good. " in several millions. "
But these are not fatal attacks by sharks resembling Jaws.
Over the 55-year period, 1,215 people reported shark attacks in the United States – but most of these attacks ended with abrasions or minor skin injuries similar to a dog bite. Only about 2% were fatal.
According to the study, this represents about 6 to 75 unprovoked attacks that occur each year in the world. Surfing and swimming were the activities most likely to occur before a shark attack, and scuba diving accounted for about 10%.
"We should think about the risk of a shark attack like a car accident," Midway said. "For example, we do not evaluate our personal car accident risk in national car accident statistics year after year." We think about our car, the weather, the road conditions and other very local factors. "
Among the 14 countries, the most dominant shark species are bull sharks, tiger sharks and white sharks. These species are of interest to researchers because of their migration patterns. But they are also sadly described as terrors for tourists in TV shows and movies.
Prediction of individual shark attacks was not the goal of the study, and it is impossible, said the researchers. However, knowing the long-term and regional trends associated with human activity could help determine the risk.
"Humans have always demonized sharks because they are elusive and live in an environment that is not native to us – the sea," said George Burgess, co-author of the study and Director Emeritus of the Shark Research Program at the Florida Museum of Natural History, in a statement. "We would like people to know that these shark attack attacks need to be put into perspective whenever they occur.This study helps us stand back and look at the bigger picture."