yego.me
💡 Stop wasting time. Read Youtube instead of watch. Download Chrome Extension

What's Driving Shark Attacks in Recife? | SharkFest


3m read
·Nov 11, 2024

[dramatic music]

NARRATOR: Along a roughly 25-mile stretch of shore, there have been more than 60 shark attacks since records began and almost half of them fatal. In fact, this small area accounts for almost 50% of recorded attacks in the entire continent. As a result, it's earned a chilling designation as South America's deadliest coastline.

[water splashes]

ANDRE AFONSO: In Recife, the shark attack problem is very serious. It's probably one of the most dangerous cities in the world for having a swim.

NARRATOR: Residents are at their wits end. I want to know why it happens here and always here.

NARRATOR: In an attempt to prevent further attacks, authorities banned surfing in certain areas, and signs line the beaches warning of the dangers of entering the ocean. But the only real way to stop this bloody barrage is to figure out how it started.

FABIO HAZIN: It's absolutely crucial to find the cause of the problem because, if we don't, we can't build a solution.

NARRATOR: So what's driving this terrifying onslaught along with Recife's shores? And could other coastal resorts be next? According to former instructor Fernando Clark, something makes diving in this area unique. And it hides deep beneath the waves. Recife is the shipwrecked capital off Brazil.

NARRATOR: The area around the attack zone is home to dozens of sunken vessels, some dating as far back as the 16th century. But according to Clark, these ill-fated ships are more than just rusty relics.

FERNANDO CLARK: The shipwrecks become a reef completely full of marine life.

NARRATOR: Fish, crustaceans, and mollusks call these down vessels home. But it's what these marine inhabitants attract that could be problematic for people.

FERNANDO CLARK: When you go shipwreck diving here, most of the time we see a lot of sharks.

NARRATOR: The presence of sharks near shipwrecks is a phenomenon that can be seen elsewhere too. In the US, sunken vessels along the shores of Oregon, Florida, and North Carolina are inhabited by these predators. The sharks are attracted to the shipwreck because of the food.

NARRATOR: So could the wrecks of Recife be responsible for luring dangerous predators near shore where people are? Clark says the answer comes down to the species of shark he sees most often on his dives. To demonstrate, he plunges into the shark-infested waters.

[water splashes]

[gentle music]

Before long, he spots just what he's looking for-- nurse sharks.

[energetic music]

NARRATOR: Nurse sharks are bottom dwellers, attracted to the crustaceans inhabiting Recife's sunken ships. Measuring up to 9 feet, they possess powerful jaws with serrated teeth. And, worldwide, they have been implicated in multiple attacks on humans. So could nurse sharks be responsible for Recife's spike? Dr. Fabio Hazin is one of the lead investigators trying to get to the bottom of what's happening along this coast. And when he analyzes the details of each incident, he comes to an important conclusion.

FABIO HAZIN: Nobody in Recife has ever reported being attacked by the nurse shark. So the shipwrecks are not at all to blame for the attacks.

NARRATOR: Instead, Hazin's analysis points to two other suspects, both of which have reputations for attacking humans. The first one is tiger sharks.

NARRATOR: Tiger sharks can grow up to 18 feet in length and weigh in at 1,400 pounds. Known for their undiscerning palates, they're equipped with sharp, serrated teeth that allow them to rip through seabirds, turtles, and even people.

[dramatic music]

NARRATOR: Perhaps even more imposing is the other culprit Hazin implicates in the spike. And that is bull sharks.

[energetic music]

NARRATOR: Bull sharks bite with the most force pound for pound of any large shark. They are fast and aggressive. And they're often found in the same shallow coastal waters as humans. So it appears tigers and bulls may be responsible for the spike. The question is, why?

More Articles

View All
Area of an isosceles triangle
Pause this video and see if you can find the area of this triangle. I’ll give you two hints: recognize this is an isosceles triangle, and another hint is that the Pythagorean theorem might be useful. All right, now let’s work through this together. So we…
Can We Fix Climate Change? | Explorer
We can’t really fix climate change. We can mitigate it. We can get to work on it. We can spread it out. We can make things better. What we got to do is stop burning fossil fuels immediately, as soon as we possibly can. Then there’s a strange effect that …
UChicago's Jim Nondorf on authentic applications to get accepted into college | Homeroom with Sal
Hi everyone! Welcome to our daily homeroom live stream. This is our way at Khan Academy of keeping everyone in touch during school closures. Obviously, as an organization with a mission of providing a free world-class education for anyone, anywhere, we pu…
Amelia Earhart Part I: The Lady Vanishes | Podcast | Overheard at National Geographic
The pilot, winging his way above the earth at 200 miles an hour, talks by radio telephone to ground stations and to other planes in the air. He sits behind engines, the reliability of which, measured by yardsticks of the past, is all but unbelievable. I m…
Identifying centripetal force for cars and satellites | AP Physics 1 | Khan Academy
So here we have something that you probably have done in the last, maybe in the last day. If we’re in a car and we’re just making a turn, let’s say at a constant speed on a road that is flat, so it’s not a banked racetrack or anything like that, what is k…
Power dissipation in resistors in series versus in parallel
A student builds a circuit with a battery and two light bulbs in series. Then the student builds a second circuit with two light bulbs in parallel. Which battery runs out of power first? Assume all bulbs have equal resistance. Assume both batteries have …