Beyond Shark Week

Kristine Stump swims with tiger sharks, bull sharks, lemon sharks, hammerheads, and more

The marine biologist is wary of human behavior that threatens to destroy the ocean’s top predators

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Dr. Kristine Stump swims alongside, and holds onto, a tiger shark during one of her research trips. Photo credit: Grant Johnson

After several glorious days of frenzied teeth-gnashing, Shark Week is about to come to an end. The Discovery Channel’s annual ratings boon is the longest running cable event in history, and it has become a cultural institution in its own right. For most of us, watching sensationalist specials like Great White Serial Killer is about as close as we’re willing to get to the species. But for marine biologist Kristine Stump, encountering sharks is both a welcome and commonplace occurrence.

Stump is a post-doctoral fellow at the Shedd Aquarium in Chicago. As a Ph.D. student, her research focused on lemon shark groups off the coast of Bimini, a Bahamian island. Almost every day, Stump would swim underwater with the lemon sharks to observe how the population was being impacted by the development of a new resort on the island. Her findings were dire: construction disturbed the underwater nurseries where the sharks raised their babies, leading to changes in diet, slower growth rate, and higher incidences of mortality.

Women in the World spoke to Stump about swimming with sharks, the widespread devastation of shark populations, and the hidden beauty of the ocean’s most fearsome predator.

Women in the World: For most people, sharks are the stuff of nightmares. You obviously don’t feel the same way. When did you first become interested in the species?

Kristine Stump: To be honest, I can’t remember a time where I wasn’t into sharks. I grew up in Florida, on the coast, so they were always sort of in my consciousness. As soon as I showed interest, my parents bought me all the shark books that I could get my hands on. I watched old documentaries … [and] Jaws. I wanted to grab my mask and go run into the water [after I saw Jaws].

WITW: That’s a unique reaction to that movie.

KS: It’s the opposite reaction to most people. But I really wanted to be Matt Hooper, the marine biologist in Jaws.

WITW: Your doctoral research focused on lemon sharks in the Bahamas. Did you have to spend time underwater with the shark groups you studied?

KS: Living in the Bahamas at a field station, we were out on the boats everyday. We were tracking the sharks, so we would put transmitters in them and track them. We would catch them, tag them, measure them, weigh them. We would do a non-lethal procedure called a stomach eversion, where we pulled their stomachs out, collect their stomach contents, put it back in, and set them free. Which is very cool. So yeah, [I was] in the water constantly with the sharks—all day everyday.

WITW: Were you ever a little worried that one might try and take a cheeky bite?

No, not at all. Not at all. I’ve been in the water with lemon sharks, tiger sharks, bull sharks, whitenose, blacktips, reef sharks, hammerheads, you name it. And I’ve never once had a problem with the sharks. In fact, the scariest moment I’ve ever had underwater was with a dolphin.

WITW: Oh, really? What happened?

KS: Given a certain set of circumstances, sharks are pretty instinctual, so you know how they’re going to react. Dolphins, they’re kind of smart enough to mess with you. So I jumped in, and there was a pod of dolphins and the big male in front just stopped on a dime. He opened his mouth fully, blew bubbles out of his blowhole, and just screamed at me underwater. He was warning me off.

WITW: Last year, you appeared in a Shark Week special called Monster Hammerhead, which was about a legendary shark that had supposedly been lurking in Florida waters for 60 years. You later told i09 that the angle of the documentary did not match the description of what you were told was going to be filmed. What happened?

KS: They filmed us working on hammerheads—tagging them, tracking them. What they filmed us doing was real research. We were tagging hammerheads by swimming down and tagging them with a pole spear, and that’s because they’re too fragile to catch. They can’t physiologically survive being captured, so we tag them by free diving. The stuff that [Discovery] showed was real science, couched in a bigger story that wasn’t necessarily something that we were working on.

WITW: And that bigger story was about a giant, 60-year-old hammerhead shark?

KS: Yes. That exceeds the maximum life span of what we know hammerheads [can reach].

WITW: Do you think propagating the image of sharks as mythical, bloodthirsty monsters does harm to the species in any way?

KS: I think sharks already have a bad enough rap. No matter how many facts you can spout off about things that are more likely to hurt you, or bite you, or kill you, and how statistically insignificant the likelihood of a shark incident is, there’s still a primal fear of sharks. So I don’t think [Discovery is] creating something that’s not already there. But the way to help is to show sharks in a different light—to talk about the science, to talk about the things we don’t know. Because there’s over 400 species of sharks, most of them people never have heard of.

[Discovery has] done a good job this year [with Shark Week]. There have been a couple of really cool shows. Alien Sharks was a really great show. It followed three sets of researchers—real shark researchers—doing deep-sea shark surveys. And that was very cool. I was very happy to see that.

WITW: Around 100 million sharks are killed every year by humans. Do you think that if we had a more nuanced perception of sharks, fewer of them would die?

KS: Certainly, because I think that if you get the general public behind a movement, that can change things. Sharks are harvested for fins, they’re targeted directly, they’re caught in by-catch. We used to have global whaling fleets, and now the general public opinion changed. So now you see an international ban on whaling. 

WITW: What is the greatest threat facing sharks right now?

KS: I would say there are two huge threats. One is unsustainable harvest. The other that often gets forgotten is habitat loss—habitat loss at various stages of development. So for example, there’s not really a targeted fishery for lemon sharks. They live on reefs. But when they’re juveniles, they live in these nurseries, and the nurseries are being destroyed. If we can’t have good, suitable nursery habitats for the juveniles, they’re not going to grow up to be the adult population. That’s true of a lot of species that use estuaries as nurseries, or go up rivers, or use these coastal areas. Development is a huge, huge problem that often gets overlooked because we always think of just direct harvest. 

WITW: The rate at which sharks are killed is obviously devastating to the species, but their deaths have a broader impact too. What do sharks contribute to the ecosystem?

KS: We need sharks. You can think of it as “top down” and “bottom up.” A shark is an indicator of a healthy ecosystem because you have your primary producers: your plants, your plankton, the things that are converting the sun into energy, into food. Those are eaten by small fish, and those are eaten by bigger fish, and then it moves up the food chain. So if you have all the pieces of the system in place, then you’ll have sharks at the top. If an ecosystem isn’t healthy enough from all its lower components, you won’t see those sharks. So if you’re not seeing sharks in the system, you know you’re looking at something that has become unhealthy. That’s what a top predator is—it’s something that is supported by all the other pieces below it. That’s from the bottom-up thinking.

As far as top-down, sharks eat mostly fish [and] other sharks. There’s some evidence that they eat the ones that are sick, the ones that are easier to catch … So it’s natural selection in progress. They are affecting the genetic structure of their prey, because they are picking off the ones that aren’t able to survive, or outrun, or hide as well.

WITW: Over the past few weeks, there has been a cluster of shark attacks in the U.S.—and in North Carolina specifically. Is something going on, or is it a freak coincidence? 

KS: The sharks are always there. That’s their habitat. There have been some theories that maybe the sharks have been following their prey—specifically in that North Carolina case. Their prey is following a certain temperature threshold, and so they’re following those prey. That’s why they’re coming into more contact with people. You also have to consider that human populations are growing, and more and more people are spending time in the sharks’ habitats. So encounters are statistically more likely to happen. Unfortunately, you have this coincidence, where a couple of incidences have been closer together, but if you look at the overall trend over many, many years, there’s no significant increase in these incidents.

The thing is, sharks are wary of humans. They really are. When we’re in the water, we’re big and weird, and we splash, and we’re gangly. [But] sharks don’t have hands. They can’t figure out what’s going on, so they bump things with their head, or they take an exploratory bite. That’s usually what happens, especially in places with murky water [like] off the coast of Florida, or off the coast of North Carolina. Sight is impaired a little bit, so it’s always a mistaken identity. There is no shark that specifically targets humans. We are not part of their diet.  

WITW: So on a scale of 1 to 10, how scared do I need to be during my next beach vacation?

KS: Zero. 

WITW: What has surprised you most about the sharks that you have encountered throughout your career?

KS: Every time I’m in the water with sharks, I’m amazed at how beautiful they are. They’re so powerful. When they come towards you, they turn, and you can just see their muscles. They’re so beautiful underwater. They’re so graceful. Like I said, I’ve never, ever had a situation underwater where I’ve been scared, because they’re so smart. I’ve been in the water where there is scum and bait all over the place, and they don’t care that I’m there. They go for the bait. They know the difference … It’s amazing just how smart and beautiful they are.

 This interview has been edited and condensed.

See the bottom of the ocean through the eyes of Dr. Stump!

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