Decrease in US shark attacks following record year may be linked to fading El Nino
The number of shark attacks in the United States has been well below normal this year, and the dissipation of El Niño may be to thank.
Last year, there were 59 shark attacks in the United Sates, which went down as the highest number of attacks on record in a year, the International Shark Attack File reported.
However, the number of shark attacks this year has dropped drastically with only 24 shark attacks in U.S. waters. Over the past few years, there has been an average of about 53 shark attacks per year in the U.S.
Accord to George Burgess, director of the Florida Museum of Natural History's International Shark Attack File, the primary reason behind this sharp decline in attacks is the fading of the El Niño pattern.
“It’s been a low year [for shark attacks] this year compared to last year, and we can pretty much directly attribute some of that reduction to the diminishment of El Niño,” Burgess said.
El Niño is a phenomenon that corresponds with warmer ocean waters in the central and eastern Pacific Ocean centered around the equator. La Niña is the opposite, corresponding with cooler ocean waters in the same region.
“Last year was an El Niño year, so we saw a lot of environmental changes,” Burgess said. “The most notable change was the warmer water temperatures along the West and East coasts of the United States.”
“Warmer water temperatures promote the movement of tropical or sub-tropical animals up the coast, allowing them to go farther north and allowing them to stay longer before winter comes around,” Burgess added.
This translates to a higher chance for sharks attacks in El Niño years since sharks inhabit coastal waters for a longer part of the year.
La Niña causes the opposite effects of El Niño, hindering tropical and sub-tropical sharks from moving well up the coast, ultimately leading to a lower number of shark attacks, according to Burgess.
With El Niño coming to an end earlier this year and with the possible development of La Niña in the coming months, ocean waters have been cooler in 2016 when compared to 2015.
This drop in ocean temperature near the coast has been a key factor in reducing the number of shark attacks in the United States.
However, water temperature is not the only factor to consider when dealing with shark attacks. There is a human element in the equation as well. A higher number of people in waters would increase the chance for shark interactions and thus shark attacks to occur.
If you are headed to the ocean and want to limit the possibility of being a victim of a star attack, here are five tips to follow.
