The 10 Most Dangerous Sharks

By: Molly Edmonds & Patrick J. Kiger  | 

That's quite a set of teeth. See more shark pictures.
Carl Roessler/Getty Images

Are sharks really dangerous? After all, you're more likely to be killed by lightning or faulty wiring on your Christmas tree than by a shark [source: McCarthy]. Death by bee sting occurs far more often than death by shark [source: Burgess]. In the water, you're more apt to drown or be injured by your own surfboard than be hurt by a shark [source: Martin].

Researchers love to throw around statistics like these to redeem sharks. Here's another juicy one: In 1987, more than 8,000 dogs bit humans in New York City, while there were 1,587 reported instances of a human biting a human in the Big Apple. That same year, there were 13 shark attacks in the entire United States [source: ISAF]. Statistically, it would seem that a person was more likely to be bit while riding the New York City subway than swimming in the ocean.


Still, sharks and the possibility of attack continue to terrify us, thanks to movies like "Jaws" and sensational news reports. For many, sharks represent the unknown and the unknowable. While we can forgive some of those 8,000 dogs for biting us, sharks don't show the same types of emotion, which makes it easy to paint them as mindless man-eaters. Sometimes the statistics support our fears. In the past few years, the number of shark attacks has risen slightly, although that's likely due to more people engaging in recreational water activities, as opposed to hungrier sharks.

Any shark that measures more than 6 feet (1.8 meters) is a potential threat to humans because it's big and because it likely has adaptations, such as more developed jaws and stronger teeth, that have enabled its large size [sources: Burgess, Ritter]. These sharks may not be specifically trolling for human flesh, but if they were to take a sample bite, they could do some serious damage.

While the most dangerous shark may always be the one that's swimming right towards you, it's worth remembering that of the almost 400 identified shark species, less than 10 percent have been implicated in an attack on a human [source: Martin]. Of the approximately 30 species that have attacked, which are the most dangerous? Let's sift through the attack statistics, the stereotypes and the sharp teeth to find out.

10: Shortfin Mako

This list won't include the biggest shark, the whale shark, which eats by filtering little pieces of plankton out of the water and is thus uninterested in humans. But this list does include the fastest shark, the shortfin mako, which has been clocked at 20 miles (32 kilometers) per hour [source: Allen].

Although the shortfin mako has only been blamed for eight unprovoked attacks and two human fatalities, it ranks second only to the great white shark for attacks on boats, notching up 20 in comparison to the great white's 95 [source: ISAF]. In one report, the mako's bite was enough to sink the boat in three minutes [source: Allen]. For this reason, the shortfin mako may be the most dangerous shark for fishermen.


Conversely, fishermen are dangerous to the mako, which is a prize catch in the game-fishing world because of its speed, aggression and long jumps out of the water. When hooked, the mako becomes extremely violent, sometimes harming the fishermen or the boat in the process. It's used to putting up a fight; its main prey, the swordfish, often attacks it in the course of the hunt. Novelist Zane Gray once wrote that a look into the mako's eyes revealed "a creature that would kill as he was being killed" [source: Lineaweaver].

Some of these incidents with fishermen are considered "provoked," so the mako ranks slightly higher in provoked attacks than unprovoked. Because the mako lives in deeper waters, fishermen and divers might be the only two groups that need to worry about this vigorously strong fish. Divers report that the mako swims in a figure-eight pattern with its mouth open as it tries to determine whether to attack [source: Compagno].

On the next page, see which shark has a taste for sailors.

9: Oceanic Whitetip Shark

The oceanic whitetip may only have seven unprovoked attacks and two fatalities on the books, but that's because it might be getting away with many of its crimes by not leaving any evidence. Marine explorer Jacques Cousteau ranked this shark as one of the most dangerous for its brazenness in evaluating prey [source: Bright].

Found in deep waters, this shark became a primary enemy during times of war, when soldiers ended up in the water after their transport was attacked. Known for being the first on the scene of a shipwreck, this shark likely gobbled up many servicemen not reflected in the statistics. Most notably, the whitetip is thought to be responsible for eating many of the men aboard the Nova Scotia, which sunk in World War II and suffered more than 800 casualties [source: Bester].


The whitetip is probably one of the most abundant large fish in the ocean. Divers who encounter the fish report that this is a shark with attitude and boldness, unperturbed by the divers' defense mechanisms. It persistently and aggressively investigates divers.

The whitetip isn't the only deep-water shark known to take an interest in whoever's bobbing in its feeding area, though. On the next page, meet the blue shark.

8: Blue Shark

Here's the good news: You don't have to worry about a blue shark stalking you while you frolic in the waves a few yards from your beach blanket. This aquatic predator, who can grow in excess of 12 feet (3.6 meters) in length, prefers to remain in waters at least 1,150 feet (350 meters) deep. That's where it finds its dinner: small bony fishes, like herring and sardines, and invertebrates, like squid, cuttlefish and octopi. It's also been known to scavenge on dead marine animals and steal from fishermen's nets.

And that brings us to the bad news: Although blue sharks aren't known to be particularly aggressive -- especially compared to their nastier cousins the bull sharks -- they won't always turn their noses up at a potential meal of human flesh, either, if you happen to be shipwrecked or floating on your seat cushion after surviving a plane crash. Reportedly, blue sharks have circled unfortunates bobbing around in their feeding grounds, and have been known to take exploratory bites [source: Florida Museum of Natural History]. That said, between 1580 and 2010, there've only been 32 (just 32!) reported blue shark attacks, including four unprovoked attacks that resulted in fatalities [source: International Shark Attack File].


In reality, blue sharks (Prionace glauca) have far more to fear from people. An estimated 10 to 20 million of them are killed by humans each year. Many blue sharks are killed when they become entangled in fishermen's nets and others are slaughtered for their fins, which are sold on Asian markets for making shark fin soup, a delicacy [source: Florida Museum of Natural History].

7: Blacktip Shark

If you're a Florida surfer, you may already be familiar with the blacktip shark (Carcharhinus limbatus), since the species reportedly inflicts 16 percent of the shark bites on surfing enthusiasts in your state. Blacktips also have chomped on humans along other parts of the Atlantic and Gulf coasts of the United States, and off the waters of South Africa and the Caribbean.

If there's an upside to this, it's that the species, which prefers depths of around 10 feet, only averages about 5 feet (1.5 meters) in length and just 40 pounds (18 kilograms) in weight, and seldom inflicts anything more than a minor wound [source: Florida Museum of Natural History]. There've been 42 documented attacks on humans by blacktip sharks, but just one resulted in an unprovoked fatality [source: International Shark Attack File].


Though blacktips usually prefer saltwater, they also are often seen near shore around river mouths, bays, mangrove swamps and in other estuaries. They get their name from the distinctive black markings on the tips of their fins. They have stout bodies with a moderately long, pointed snouts and high, pointed first dorsal fins. They're dark gray-blue or brown on their upper bodies, with white underbellies and a distinctive white band across their flanks. Blacktips feed primarily on small schooling fishes like herring and sardines, but they also eat bigger bony fish like catfish and grouper and have been known to make a meal out of some types of small sharks, stingrays, crustaceans and squids.

We'd be remiss if we didn't add that like many other shark species, blacktips have more to fear from humans than the other way around. They're caught by fishermen, who sell their meat for human consumption or to be used as fish meal to feed animals. Their fins are also sold in Asian markets for making soup. The International Union for Conservation of Nature (IUCN) classifies blacktips as "near threatened" around the world and "vulnerable" in the northwest Atlantic region [source: Florida Museum of Natural History].

6: Nurse Shark

The nurse shark doing what it does best -- resting.
The nurse shark doing what it does best -- resting.
Wolcott Henry/National Geographic/Getty Images

If the nurse shark were a person, it might have a chip on its shoulder about its name, which isn't nearly as ferocious-sounding as "bull" or "tiger." But while the nurse shark certainly doesn't tend to human beings like an RN, its name is somewhat appropriate insomuch that the shark is generally non-aggressive and typically swims away from people. The species (Ginglymostoma cirratum), which grows to between 8 and 9 feet (2.4 and 2.7 meters) in length, is concentrated in shallow waters in the Caribbean, and off the coast of south Florida and the Florida Keys, but is also found along the Atlantic and Pacific coasts of the Americas [source: Florida Museum of Natural History].

Fortunately, even in the rare instances when a nurse shark does attack a human -- so far, 52 times, with no recorded fatalities -- the bite isn't powerful enough to be lethal [source: International Shark Attack File]. The downside is that the nurse shark's small mouth is attached to a large pharynx that enables it to suck up food and latch onto it. In fact, its grip is so vicelike that, in some cases, rescuers have had to use surgical instruments to free victims.


Fortunately, humans aren't the nurse shark's preferred meal, of course; the species feeds mainly on stingrays, octopi, squids, clams and crustaceans. They're nocturnal animals that rest on sandy bottoms or in caves and crevices during the day, and they often gather in groups of as many as 40. Nurse sharks have rounded, stubby heads with set-back eyes, and long caudal (tail) fins, which account for more than a quarter of their total length. They range from light yellowish tan to dark brown in color, and young nurse sharks have small black spots on their bodies. While nurse sharks are not endangered, their population in Florida has decreased in recent decades. [Source: Florida Museum of Natural History]

5: Requiem Sharks

Requiem sharks actually are a family of 12 genera and approximately 50 species. They have a funereal-sounding name, and for spear fishermen, in particular, they can be a lethal menace. That's because fish skewered and struggling on a spear emit low frequency vibrations, which requiems can detect with their highly sophisticated sensory organs. Once they've arrived in the vicinity of the catch and can smell blood, their aggressive instincts can take over. That's not a good thing, if you happen to be in the water with them, because the strong-swimming, torpedo-shaped predators, who travel either solo or in groups, have big mouths filled with sharp, serrated teeth [source: Randall]. Various types of requiem sharks have attacked humans 56 times, with seven unprovoked fatal attacks on record [source: International Shark Attack File].

What makes the sharks even more frightening is that a few of requiem species, such as the grey reef shark, have a distinctive threat posturing. The sharks will swim laterally, toss their heads in an exaggerated fashion, arch their backs with their pectoral fins held downward, and snap their jaws menacingly. If you see a shark doing that, it's best to move slowly away. Requiem species vary in size, but the biggest can exceed 24 feet in length, often making them the biggest bullies on the block [source: Beller].


If there's a silver lining to all this, it's that requiems are voracious eaters who normally dine on a lot of other creatures besides humans, including sharks and rays, squid, octopuses, lobsters, turtles, marine mammals and sea birds [source: Randall]. Large and fierce members of the Requiem family, like the bull shark and the tiger shark, are especially dangerous to humans. We'll get to them in a couple of pages.

4: Sand Tiger Shark

Researchers who've observed sand tiger sharks say they generally aren't aggressive toward humans unless provoked, but that's not much consolation if you're a fisherman and find yourself confronted with the predator's prominent, jagged-looking teeth [source: Florida Museum of Natural History]. Sand tigers have attacked humans 77 times, though, miraculously, only one of the attacks proved fatal [source: International Shark Attack File].

The species (Carcharias Taurus) is found in most warm seas throughout the world, except for the eastern Pacific. In the western Atlantic Ocean, sand tiger sharks range from the Gulf of Maine to Argentina, and are commonly found in Cape Cod and Delaware Bay during the summer months. They're most often found close to shore, at depths ranging from 6 to 626 feet (1.8 to 190 meters), but are also found in shallow bays, coral and rocky reefs, and sometimes also in deeper areas around the outer continental shelves.


Sand tiger sharks are large and bulky, with flattened conical snouts and long mouths that extend behind the eyes; they sometimes have dark reddish or brown spots scattered on their bodies. Females can reach a maximum length of more than 10 feet (3 meters); males are usually just under 10 feet.

As previously mentioned, sand tigers have a hearty appetite -- for herrings, mullets and rays, among other things -- and they sometimes hunt in schools and cooperate by surrounding and bunching their prey. Sand tigers are fished for food in the north Pacific, northern Indian Ocean and tropical west coast of Africa. The IUCN classifies sand tigers as a "vulnerable" species [source: Florida Museum of Natural History].

3: Tiger Shark

Tiger sharks aren't looking to specifically eat humans, but then, they weren't specifically looking to eat lumps of coal, cans of paint, packs of cigarettes or Senegalese drums either. These items have all been found in the bellies of tiger sharks (Galeocerdo cuvier), which are known for their ability to eat just about anything [source: Parker]. So while other sharks may just want a sample to find out if a person is edible, the tiger shark is less likely to let go once it's taken a bite.

If a tiger shark does decide to continue eating, you're in for an unpleasant experience, to say the least. Their jaws have elastic muscles, which allow them to swallow pieces of prey much larger than what might seem possible. And little can be done once you're in the grip of the tiger shark's razor-sharp teeth, which can chomp through anything. Many a crunchy sea turtle has fallen prey to those teeth despite a hard, protective shell.


Those teeth, which can puncture and rip apart prey in a matter of seconds, have been responsible for a total of 157 attacks, including 27 unprovoked fatal attacks [source: ISAF].

Which shark is dangerous because it can lurk near oblivious swimmers? Find out on the next page.

2: Bull Shark

The bull shark's statistics are pretty impressive. With a total of 121 attacks, which includes 25 unprovoked fatal attacks, this shark has already earned its spot as one of the three most dangerous sharks. The bull shark is as aggressive as its name implies, and one of its victims has described an attack as similar to being hit by a truck [source: McCarthy].

Technically, the tiger shark surpasses the bull shark in terms of numbers of attacks and fatalities. But many researchers think that the bull shark gets off easy in terms of statistics and may actually be responsible for many of the attacks pinned on tiger sharks and great white sharks. Most notably, the 1916 shark attacks on the New Jersey coast, thought to be the inspiration for "Jaws," were more likely conducted by a bull shark, rather than the great white that took the blame [source: Parker].


The bull shark is dangerous simply because it's more likely to come into contact with humans than some of these other sharks. It can live in both salt and freshwater, and the bull has been spotted in water so shallow that humans are walking around in it. What's more, they're fairly territorial about their homes, so a person out for a simple stroll could be agitating bull sharks without even knowing it.

If you've seen the movie "Jaws," you can probably guess what shark tops our list. Click to the next page to find out if you're right.

1: Great White

A great white shark breeches.
A great white shark breeches.
Stephen Frink/Getty Images

You don't become the subject of a movie like "Jaws" without being dangerous in real life as well. Indeed, the great white shark (Carcharodon carcharias) leads all other sharks in attacks on people and boats, as well as fatalities. Currently, the great white shark has been connected with a total of 403 attacks, including 247 unprovoked attacks and 65 fatalities [source: ISAF].

In 2001, "Jaws" author Peter Benchley claimed that he couldn't have written the book in this day and age, knowing what he knows now about great white sharks [source: McCarthy]. The great white is just not the mindless killing machine that was depicted on the silver screen. This shark is extremely curious, though, and may bite humans to determine if they would make a good meal. They generally don't return for seconds, though, because a human simply isn't a very good meal for them. These sharks much prefer the fatty blubber of seals and sea lions.

While some scientists say that surfers on their boards may look like seals from below, it may just be a youthful mistake. Some researchers think that the sharks mistaking surfers for seals are the juveniles of the species, who are in the first stages of adding seals and sea lions to their diet [source: McCarthy].

Whether it's mistaken identity or not will certainly matter very little to the poor person who does get trapped in these infamous jaws. As for being a "taste bite," the great white takes a pretty big taste, as it's able to consume 20 to 30 pounds (9 to 14 kilograms) of flesh with each bite, with the force of each bite measuring over 1 ton per square inch [source: Dingerkus]. With one bite like that, death can occur from bleeding to death or internal organ damage.

Most swimmers needn't worry about running into a great white shark though; they usually stay in deep waters and are fairly rare. But that elusiveness serves to make them even more frightening to some.

To learn more about sharks, dangerous and otherwise, have a look at the links on the next page.

Originally Published: Jun 5, 2008

Dangerous Shark FAQ

What is the most dangerous shark?
Bull sharks are one of the most dangerous sharks in the world. They’re very similar to their more infamous relatives, tiger sharks and great whites, both of which are considered equally as dangerous.
Which shark has killed the most humans?
As of April 2021, the great white shark - the species portrayed in the film “Jaws” - is responsible for the highest number of unprovoked attacks with 333 total events including 52 fatalities. However, it’s important to note that the risk of being bitten or killed by a shark remains extremely low.
Do hammerhead sharks attack people?
Hammerhead sharks rarely ever attack human beings. In fact, humans are more of a threat to the species than the other way around. Only 16 attacks (with no fatalities) have ever been recorded globally.
Which is more dangerous: tiger sharks or bull sharks?
Unprovoked attacks by tiger sharks slightly exceed those of bull sharks. As of April 2021, tiger sharks are responsible for 131 attacks, including 34 fatalities while bull sharks have attacked 117 times resulting in 25 fatalities. However, it’s worth noting that humans have a higher probability of coming into contact with a bull shark compared to other species because they tend to swim in the same areas as humans - shallow water.
Is it safe to swim with tiger sharks?
Most experienced divers agree that seeing a shark on a dive is a treat. Still, practicing safe behavior around them helps ensure a positive experience. The risk of harm from a shark encounter is statistically pretty small, but they are apex predators and should be treated with respect.

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