Shark Facts

Raise awareness for why people need sharks

For 400 million years, sharks have roamed every ocean on Earth. Few species have thrived on our planet for as long — and even fewer have been as misunderstood. The truth is that these mysterious, magnificent apex predators are essential to keeping the balance of marine ecosystems — and in many communities, help boost local economies. Sink your teeth into shark facts —and learn why #PeopleNeedSharks.


Fact 1: Shark tourism generates more than US$ 300 million annuallyJump to references1

Sharks boost local economies through ecotourism. Over the last few decades, public fascination with sharks has supported businesses like boat rentals and diving companies in places such as the Bahamas, South Africa and the Galápagos Islands. These activities are said to provide 10,000 direct jobs globally. Tweet this fact


Fact 2: Humans kill up to 100 million sharks per yearJump to references2

Despite their scary reputation, most sharks are not dangerous to humans — in fact, they rarely attack people. If anything, sharks should be afraid of humans — many species of sharks are threatened by human activities. Sharks worldwide are the target of vast overfishing to supply the enormous demand for sharkfin soup, a delicacy in some Asian countries. But there is a flip side. Tweet this fact


Fact 3: The largest sharks are nearly 60 feet long

Whale sharks — docile filter-feeders that passively scoop up small fish, invertebrates and plankton — can get up to 59 feet (18 meters) long.Jump to references3 That makes them the largest sharks — and fish — in the world.Jump to references4 By comparison, whale sharks' fearsome cousins, great whites, can grow to about 23 feet (7 meters). Tweet this fact


Fact 4: Shark behavior changes when the moon is full

A study of grey reef sharks in Palau, Micronesia, showed that sharks dive deeper during a full moon than at any other time in the lunar cycle.Jump to references5 This "lunatic" behavior is thought to be tied to similar diving behavior exhibited by the shark's prey — meaning that sharks are following their food source. Tweet this fact


Fact 5: Hammerheads can see in 360 degreesJump to references6

Thanks to their oddly shaped heads and the unusually wide distance between their eyes, hammerhead sharks possess excellent binocular vision, enabling them to gauge both depth and distance when scanning the sea for their next meal. What's more, by waggling their heads back and forth, they can spot prey (or danger) all around them — above, below and even behind. Tweet this fact


Fact 6: Sharks were around before the first trees

According to the fossil record, sharks have been patrolling Earth's oceans for at least the last 400 million yearsJump to references7, with some estimates dating back 450 million years.Jump to references8 That makes them slightly older than trees, which appeared on Earth about 390 million years ago.Jump to references9 Tweet this fact


Fact 7: 90% of all sharks died off 19 million years ago

Having survived at least four global extinction events — including the one 65 million years ago that wiped out the dinosaurs — sharks were nearly lost for good 19 million years ago. While the nature of this mysterious die-off event — what caused it and why it didn't affect all species around the globe — begs further study, the fossil record shows that worldwide shark numbers dropped by 90 percent and up to 70 percent of all shark species were lost.Jump to references10 Tweet this fact


Fact 8: Some sharks can walk on dry land

Epaulette sharks, sometimes known as 'walking sharks,' can use their fore fins to amble across the beach — up to 100 feet (30 meters)Jump to references — in search of crabs and other creatures left behind by the retreating tide. And there's no rush: These sharks can survive for up to an hour outside of the water. Tweet this fact

Fact 9: A great white's bite force is nearly 25 times stronger than the average human's

Bite force measures how strongly an animal can clamp down on its prey. In humans, the average bite force is about 160 pounds per square inch. For great white sharks, researchers estimate a whopping 4,000 pounds per square inch.Jump to references12 While no sea creature chomps down harder than the great white, there is one on land: the Nile crocodile, with a crushing bite of 5,000 pounds per square inch. Tweet this fact


Fact 10: Sharks are always growing new teeth

Because they are lightly anchored in a jaw made of cartilage rather than bone, shark teeth can come loose, especially during attacks on prey. A great white shark can lose up to 35,000 teeth in its lifetime.Jump to references13 But sharks never stop growing new teeth. They have multiple rows of teeth in their jaws. So, when a tooth is shed it is replaced — in as little as 24 hours — by a new one, which moves forward to replace it — like a biological conveyor belt. Tweet this fact


Fact 11: Shortfin makos are the fastest sharks in the world

These sleek, streamlined hunters can reach speeds of 50 miles per hour (80 kilometers per hour)Jump to references14, though some estimates put that number closer to 62 mph (100 km/h).Jump to references15 Either way, that's much faster than any human can manage: Top Olympic swimmers can motor through the water at only about 5 mph (8 km/h).Jump to references16 Tweet this fact


Fact 12: Greenland sharks are the slowest sharks in the world

Also known as 'sleeper sharks' due to their laggardly nature, Greenland sharks cruise the chilly waters of the Arctic and North Atlantic at about 0.76 miles per hour (0.34 meters per second) — with bursts up to 1.7 mph (0.74 m/s).Jump to references17 This is much slower than their top prey, the Arctic seal, so scientists surmise the sharks likely wait until the seals are asleep before attacking. Tweet this fact


Fact 13: Greenland sharks will outlive us all

Greenland sharks aren't just slow — they can live for centuries. In fact, scientists estimate their life span is at least 272 yearsJump to references18, making them the longest-living vertebrates known to science. Tweet this fact


Fact 14: Sharks have a shocking sixth sense

Part of what makes sharks such effective hunters is their ability to sense the minute electrical fields that every living creature emits. Special, electrically sensitive organs called ampullae of Lorenzini allow sharks (and skates and rays) to detect very faint electric charges. Great whites can sense a charge as weak as one millionth of voltJump to references19 — helping them zero in on prey that they can't see or even smell. Tweet this fact


Fact 15: Nurse sharks have a cheeky way of breathing

Some of the more recognizable shark species — great white, tiger and whale sharks, to name just a few — risk suffocation if they remain still too long. That's why they're always on the move, drawing water over their gills so they can breathe. Other species, like nurse sharks or wobbegongs, pull water through their mouths and across their gills with a technique called “buccal pumping,”Jump to references20 which allows them to remain motionless for long periods of time and ambush their prey. Tweet this fact


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