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Americans are spotting more sharks in the water. Here's why that's a good thing
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2023-07-29 18:18
It's that time of year again: the thick of summer when sharks have caught America's attention.

It's that time of year again: the thick of summer when sharks have caught America's attention.

Unwanted interactions and shark sightings have made national headlines, and shark bites in popular tourist destinations have prompted temporary closures. In New York, Gov. Kathy Hochul deployed dozens of shark-monitoring drones to parts of the state after Long Island authorities repo rted five non-fatal shark bites over two days.

It may feel like you've been hearing about these large creatures more often this summer, and that just might be the case. Experts say that while estimating population numbers is difficult, there are signs that some shark populations off US coasts are slowly rebounding after decades of dramatic declines -- the result of longtime conservation efforts across the country that are beginning to pay off.

"Sharks are coming back. Their numbers are growing," said Dr. Bob Hueter, chief scientist for OCEARCH, a nonprofit ocean research and education organization. "They're not overpopulated, they're not even probably close to what they were back in the 1940s and 1950s. But they are making a comeback."

But do more sharks make American beaches more dangerous?

Actually, no. But it will take some getting used to, experts said.

Here's what to know.

Are there more sharks in American waters than the past few decades?

Experts, cautiously, believe so.

Up until the late 1960s, shark numbers remained relatively stable off US shores before they began to drastically plummet as a result of overfishing, bycatch, destruction of habitats and declines in some shark species' prey.

By the late 1980s, roughly two-thirds of shark populations in American oceans had vanished, said Hueter, who has been studying sharks for more than five decades.

Hueter was among the conservationists who pushed for shark protections including the 1993 Fishery Management Plan for Sharks of the Atlantic Ocean, which set up restrictions around all US Atlantic federal shark fisheries and became the base for many rules still in place today. It also prohibited shark finning -- the hunting of sharks for their fins. The practice was later banned across the United States. In 1997, the US established the prohibited shark species group, which barred the possession, sale and purchase of several shark species, including white and sand tiger sharks. More than a dozen shark species remain on that list. And protections like the Marine Mammal Protection Act of 1972 helped restore the animals sharks feed on, including gray seals in the Northwest Atlantic where white shark populations are, as one outlet put it, "surging."

"These measures were put into place and now here we are 30 years later, and we are seeing the resurgence of not only the white shark but also many of the other species," Hueter said. "The fact is, we're resetting our oceans and we're restoring ecological balance by bringing these animals back."

But before our collective sigh of relief, it's worth noting sharks are not out of the woods by any means.

Globally, their numbers remain grim.

A 2021 study found over a third of sharks, rays and chimeras, a type of fish, are threatened with extinction, and in many parts of the world, sharks are still overfished. Every year, humans kill 73 to 100 million sharks for their fins, according to the Shark Research Institute.

How do we count sharks?

It's really, really hard.

Methods like tagging or collecting information from fishermen have their limitations: Some sharks may get tagged because they swim closer to the surface than others that prefer deeper waters, and reports from fishermen may be biased, since they often travel to locations with plenty of fish, said Gavin Naylor, director of the Florida Program for Shark Research at the University of Florida.

Information can also come from surveying those who are regularly keeping an eye out on the waters, like lifeguards and pilots.

"We've looked at lifeguard sighting records over the last 25 years and we've noticed in the last 10 years, numbers of shark sightings have gone up," said Chris Lowe, director of the Shark Lab at California State University, Long Beach.

"I've talked to pilots, either helicopter or fixed-wing pilots, that have been flying over Southern California for decades," he said. "They all tell me they have never seen more sharks in their life than they have in the last eight to 10 years."

Do more sharks = more bites?

First, let's get one thing out of the way: The risk of being bitten by a shark remains exceptionally, remarkably, incredibly low. (Seriously, your chances are 1 in more than 3 million.)

Sharks simply are not interested in eating humans.

"If sharks ... wanted to bite people, I think we'd probably have about between 10 and 20,000 shark bites a day," said Naylor. "But they spend their entire time trying to avoid us."

Between 2012 and 2021, there was an average of about 76 unprovoked shark bites across the globe annually, less than 8% of which were fatal, according to data from the International Shark Attack File. (Researchers place an emphasis on the unprovoked bites because they make up the overwhelming majority of bites, and can shed light on sharks' behavior. They include accidental bites when sharks are hunting for fish in waters with low visibility. About 60% of all bites the ISAF records are in low-visibility waters, Naylor has said.)

And though there are more sharks in the water and more Americans flocking to beaches because of warming temperatures, last year saw a decrease in unprovoked shark bites, tying with 2020 -- when many beaches closed due to Covid-19 -- for the fewest number of incidents in the past decade.

So while sharks and Americans may be coming more in contact with each other, the rate of shark bites -- in other words, their frequency -- has not gone up. (And it can stay that way, Naylor said, if people practice simple precautions and stay aware of their surroundings.)

To test that theory, researchers from the Shark Lab flew drones over 26 southern California beaches once a month for roughly two years and noticed something striking: People and sharks were, more often than not, swimming peacefully just feet away from each other.

"At those sites, people and sharks were together 97% of the days that we surveyed. On a given survey day, there were probably half a dozen to a dozen times when a juvenile white shark was within 60 feet of a person in the water," said Lowe, who co-authored the study.

Not a single bite was reported in that time period, the study says, proving more sharks do not have to mean a higher bite rate.

So, how can we best coexist?

Information is power. The more people know about where sharks are and how they operate, the less likely they are to get bitten, scientists say.

Drones, like those deployed across New York beaches, are among the most helpful bite-prevention tools and can help inform beach crowds when sharks are circling nearby, experts say.

But there are also individual measures anyone can take to keep safe. Stay in clear water and avoid areas with low visibility. And if you see schools of fish (especially if they're jumping out of the water), get out of the water or move further away to avoid any accidents.

"We have to change our approach to using the ocean because we've had 50 years of the oceans being not what they should be, with less sharks, less fish," Hueter said. "As we put things back, we have to recalibrate our understanding of what the ocean is."

"You have to think of going into the ocean like you go into a national park, where there's bears or mountain lions and take the proper precautions," he added. "Having said that, your risk is still incredibly low of ever having a problem. You might see a shark go by, if you do, just remain calm and enjoy the view because you may never see that again."

So instead of fearing them, cheer them on -- but maybe from a distance.