Are shark attacks on the rise? | The Excerpt

On a special episode (first released on July 3, 2024) of The Excerpt podcast: A recent spate of shark attacks on both coasts have swimmers and surfers concerned. But are these Jaws-esque fears warranted? As Americans head to the beach en masse, we look at whether their proximity to beachgoers is cause for alarm. Stephen Kajiura, a professor of biological sciences at Florida Atlantic University, explains how shark behavior might be changing and how to stay safe this summer.

Hit play on the player below to hear the podcast and follow along with the transcript beneath it. This transcript was automatically generated, and then edited for clarity in its current form. There may be some differences between the audio and the text.

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Taylor Wilson:

Hello and welcome to The Excerpt. I'm Taylor Wilson and today is Wednesday July 3rd 2024. A recent spate of shark attacks on both coasts have swimmers and surfers concerned. But are these Jaws-esque fears warranted? As July 4th celebrations kickoff and Americans head to the beach, we look at how shark behavior has been changing and whether their proximity to beachgoers is cause for alarm. For more, I'm now joined by Dr. Stephen Kajiura, a professor of biological sciences at Florida Atlantic University. Dr. Kajiura, thanks for joining me today on The Excerpt.

Dr. Stephen Kajiura:

My pleasure. Thank you.

Taylor Wilson:

So I want to just start here. Just generally speaking, how common or frequent are shark attacks? And is the frequency of attacks increasing?

Dr. Stephen Kajiura:

So in general, shark attacks are very rare and it doesn't happen very often at all, but it seems like there's been a lot. Just recently in the last few weeks we've had this spate of bites, but still in reality it's a small number. And I think part of the problem is that when you have a small number of bites in close temporal proximity, people tend to ramp that up and assume that there's something bigger going on. But in general, we're not much different than we have been in the past in terms of total number of bites overall. So it's not like there's been an uptick this year, at least not yet.

Taylor Wilson:

So I do want to just go through a couple of these high profile incidents and pick your brain on them. We did recently learn that surfing legend and actor to Tamayo Perry was tragically killed in a shark attack in Hawaii. Did you hear about this incident and what do we know about this?

Dr. Stephen Kajiura:

I don't know much other than the fact that ocean rescue went out and pulled him back. By the time he was back to the beach, he was pronounced dead. I unfortunately don't know much about the incident. But in Hawaii you have a lot of big sharks, big tiger sharks for example, and they're responsible for bites on people. And when a big tiger shark bites, the injuries are dramatic. It's not like a little nip. It can do dramatic tissue damage and people will very quickly bleed out, for example. And so that's one of the big concerns is if they have big sharks like that and you get bitten, there's very little that you can do to stop it.

Taylor Wilson:

And earlier this summer, three swimmers were attacked and injured by sharks on the same day within miles of each other off the coast of the Florida Panhandle. What do we know about this incident and why did these attacks happen so close to each other in terms of time and location? We've heard that heat might be responsible.

Dr. Stephen Kajiura:

So in this case, my understanding is that the one woman was bitten by herself and one shark was to blame. And then was a 90 minutes later, a few miles down the beach, two other children were bitten, some teenagers. And they were bitten right beside each other. So the shark came and bit one, came around immediately and bit the other. Again, extensive tissue damage to all of these individuals. And these were big sharks. We think in the one case, the one shark was a tiger shark and the other shark was a bull shark. So two different sharks responsible, but since the two girls were next to each other, they were bitten in quick succession there. This again is relatively unusual. You don't get sharks coming in and biting people repeatedly. And I think just because the two girls were right beside each other and once the shark bit one, there was blood in the water and that shark was able to go back in and be excited and bit the other one who was right there. I think that's what happened in that instance.

Regardless, it's a tragedy when these people are bitten by the sharks, they were just going to the beach to have a good time. I think one of the things to consider here is that in this case again, the woman was bitten by a big tiger shark and the two girls were bitten by a bull shark. Again, with all of these sharks, big teeth, big jaws. And teeth that are designed to excise chunks of flesh, not just puncture wounds, but take out big chunks of tissue. And that's why I think there was so much tissue damage in these instances compared to a lot of the bites that we get along say the East Coast of Florida where it's typically a bite, puncture and then let go and there's very little actual damage to the person.

Taylor Wilson:

It's not a coincidence that I mentioned Florida, Florida tops the list in the US When it comes to shark attacks. What is it about the Sunshine State, where you're based Dr. Kajiura, that really brings the sharks out?

Dr. Stephen Kajiura:

Well, I think one of the great things about Florida is that we're surrounded by water, both on the East Coast and on the Gulf side. Panhandle, we're adjacent to the beach all around. And so the vast majority of the Florida population is next to a beach. So as a result of this, we have a lot of people going into the water and there's always sharks in the water. And so necessarily when you have more and more people going into the water, you're going to increase the probability that something is going to happen. And I think because Florida's a year round beach destination, you have this scenario whereby people are more likely to be bitten here simply because there's so many people in the water all the time. You contrast that maybe somewhere like California, you might have a large number of people in the water in the summertime, and it gets pretty chilly in the winter, not as many people in the water. So the number of potential bites is necessarily diminished.

Taylor Wilson:

So why do sharks attack humans generally? I've heard they mostly do so out of confusion or curiosity, is that correct?

Dr. Stephen Kajiura:

Well, there's a couple of different scenarios that I want to run through. One is bites by smaller sharks and one is bites by much larger sharks. And so the bites by the smaller sharks are by far the most common. And here you have sharks that are feeding primarily on little bait fish, little fish the size of your hand. When these little bait fish are flashing in the shallow waters, the sharks will see this little bright flash and come in and bite at it. And sometimes when people are splashing in the water, the palm of your hand or the sole of your foot could catch the light and look like a little bait fish. And that's why people get bitten by these smaller sharks most often.

But that's one type of bite. I want to contrast that to another type. And that's from much bigger sharks with much bigger teeth and they do much more extensive tissue damage. And here you have things like big bull sharks or tiger sharks or white sharks farther north. And there you have animals that are coming in maybe even to feed on smaller sharks. Or up north, white sharks feeding on seals, for example. And there when these larger sharks come in and take a bite out of a person, it does much more extensive tissue damage and that's the fatal bites. And so there's very few of those, much more of the bites by its smaller sharks. But of course the bites by the smaller sharks, although it makes your day uncomfortable, it's not going to kill you.

Taylor Wilson:

That's a helpful explainer there. I'm curious about climate change. Has climate change led to sharks swimming closer and closer to shore to find food? Or what role might that be playing here?

Dr. Stephen Kajiura:

It's interesting that if you look at the migration of something like a blacktip shark, we know they come down to South Florida in the wintertime and then as the temperature starts to warm up in the spring, they migrate north. And by this time, if you're there getting close to Long Island, New York, and so they're spending the summers up there, then when the temperature starts to cool, they come south again. What's happened though in just the past decade is we've seen a rise in water temperature to the point where the sharks are not going quite as far south. They're finding their preferred temperatures, maybe mid Florida. Why go all the way down to Miami if the water's just fine off Cape Canaveral or something? And so they're not going as far south.

And in the summertime they're actually going much farther north. They never used to go beyond, say, Delaware. Now they're going all the way up to Long Island, you see our sharks hanging off Montauk. And so they're going much farther north than they ever did before. And so the whole range is shifting in response to warming oceans. And as a result of this, we're going to see more bites farther north. New York is going to see, I'm predicting, a greater number of bites than they've seen in the past simply because more sharks are going up there now. And people along the beach have never had to worry about this before, but now it's something that they do need to be concerned about, something to be aware of at least when they go to the beach.

Taylor Wilson:

So Dr. Kajiura, what can you tell swimmers or surfers or those in the water to do if they notice a shark nearby? And what should swimmers do if they're actually attacked?

Dr. Stephen Kajiura:

So again, this breaks down into the two types of sharks. We've seen people just wandering around in the water, having a good time and seeing a fin go by right between them and the shore. And that's definitely disconcerting. If it's a smaller shark, again, I would quietly move my way out of the water onto the beach. Don't make a big splash, don't make a big fuss, just get out of there as quickly as possible. What we often see though are larger sharks offshore that are maybe hunting on seals off Long Island, for example. In that scenario, you've got a much bigger shark, has a lot more potential to do damage. Again you want to get out of the water as quickly as possible, inform lifeguards, they've probably already seen it, get people out of the water because that has real danger.

Smaller shark, it's likely to just check you out and go away. Bigger shark, much more likely to have the potential to do serious damage to someone. If you do happen to find yourselves being bitten by a shark, do anything you can to make that shark life uncomfortable. Punch it in the nose, punch it in the eyes, punch it in the gills, use your hand to pry the snout off your arm. Whatever it takes, get your body out of that shark and then get back to the beach as quickly as possible. I always tell people when you go to the beach, go somewhere swimming where there's a lifeguard stand nearby. So in case anything does happen, you've got immediate first aid available and you've got a pair of eyes watching the water.

Taylor Wilson:

Increasingly frequent drone footage shows sharks being relatively peaceful around humans and also a lot closer, Dr. Kajiura, than we might think they are to humans in the water. I'm curious, have you seen these videos? You know what I'm talking about? And can these types of videos maybe help calm people's fears about shark attacks? I know when I see them, I often think, hey, this might be a lot safer than people think.

Dr. Stephen Kajiura:

Yeah, I've seen this footage, I've shot some of that footage myself with a bunch of sharks down here. And people are in the water, totally oblivious, don't even realize that there's sharks around them. And I remind people, "You were having a great day at the beach. You had no idea. You were having lots of fun. You had nothing in the back of your head to suggest that there was any danger and yet there were a dozen sharks around you." And so I encourage people to go to the beach, to have a good time because you're probably have been seen by sharks or in close proximity to sharks on a number of occasions without ever knowing it.

I don't think that it's something we need to be concerned about. If the sharks wanted us on the menu, we would see a huge spike in shark bites. But we're not part of their natural menu. And for the most part, we're these large, gangly, loud, slashing animals in the water and they basically just are curious, say, what is that? I've never seen anything like that. And then swim away and leave us alone. Hopefully people see these videos and say, "Yeah, there's sharks all the time. Maybe we shouldn't be as concerned about them."

Taylor Wilson:

And finally, Dr. Kajiura, what's the most important thing you want people to know or remember about shark safety?

Dr. Stephen Kajiura:

If I could give one takeaway message, it would be that you've probably been in the water with sharks without even realizing it and you had a great time. So I would encourage you to go back out to the beach and have a good time. Be careful, be cognizant of what might be around, check with the lifeguards, watch for the hazard flags. And if you're swimming, swim somewhere where there's other people there. So you're not the only person around. If you see a big ball of bait fish, don't swim in there. You're asking for trouble because that's what the sharks are coming to feed on. Stay somewhere where you've got quick access to medical attention if needed. And by all means, don't make this the overarching concern of the summer. The number of shark bites is tiny. And so go out there and have a good time and realize that your chances of actually having a negative encounter are vanishingly small. So don't let that overwhelm your summertime enjoyment.

Taylor Wilson:

All right. Dr. Stephen Kajiura joining us talking through shark attacks. I really appreciate your insight and perspective on this. Thank you, Dr. Kajiura.

Dr. Stephen Kajiura:

Great. Thank you so much.

Taylor Wilson:

Thanks to our senior producer Shannon Ray Green for her production assistance. Our executive producer is Laura Beatty. Let us know what you think of this episode by sending a note to podcasts@usatoday.com. Thanks for listening. I'm Taylor Wilson. Back tomorrow morning with another episode of The Excerpt.