30 Facts about Sharks
Sharks have ruled the oceans for millions of years, from tiny reef dwellers to massive great whites.
Not all of them are fierce hunters. Some feed gently on plankton, but all of them play an important role in the marine ecosystem.
Here are 30 fascinating facts that reveal just how incredible these creatures really are:
1. The whale shark is the world’s largest fish and is estimated to live up to 150 years, making it the longest-living creature on earth.
2. The tiger shark is considered to be one of the most dangerous sharks, as it is the most common large shark and will eat anything that fits into its mouth.
3. Spiny dogfish sharks travel in large schools of hundreds or even thousands, helping protect them from predators despite their small size.
4. Measuring just 17 centimetres, the dwarf lanternshark is the world’s smallest shark, and it even glows in the dark!
5. The shortfin mako shark is the fastest shark and one of the fastest fish in the world, reaching speeds of up to 50km per hour.
6. Hammerhead sharks have a uniquely shaped head, which gives them 360-degree vision and superior sensory detection.
7. Nurse sharks are slow-moving, bottom-dwellers that usually feed at night, using their strong suction to vacuum up fish, crustaceans and other prey.
8. The thresher shark has the longest tail of any shark. Its tail can be as long as its entire body, which it uses to stun prey.
9. The bull shark can live in freshwater and the ocean, venturing into rivers, lakes, and lagoons.
10. Tiger sharks have two uteri, allowing them to give birth to multiple pups at a time, sometimes up to 80 in a single litter.
11. Blue sharks are among the most threatened sharks in the world. Overfishing and the shark fin trade have led to a rapid decline in their numbers.
12. The frilled shark's lizard-like head, rounded snout, and circular mouth filled with more than 300 spiny teeth have earned it the nickname of the modern Loch Ness monster. Also, due to its ancient ancestry and primitive characteristics, it has been described as a living fossil.
13. Whale sharks are known to have massive families, and females can give birth to up to 300 pups in one litter.
14. Great white sharks have incredible eyesight. They can see both during the day and at night, and research suggests they can even perceive some colours, giving them a real advantage when hunting.
15. Sharks have been around for over 400 million years, long before humans, dinosaurs, and almost everything else with a backbone.
16. How baby sharks are born depends on what species they are. Some, like tiger sharks, are born live, while others, like horn sharks, hatch from egg cases known as ‘mermaid’s purses.
17. Angel Sharks, also known as sand devils, dig themselves into piles of sand and then use this cover to catch unsuspecting prey.
18. Some female sharks use sperm from multiple males to fertilise a single litter. This keeps the gene pool going and results in pups being half-siblings even though they are born at the same time.
19. Sharks have tiny nodules on their noses known as ampullae of Lorenzini, which assist them in their sixth sense, electroreception. These nodules sense electrical pulses in the water that help them navigate and locate their prey.
20. Despite their massive mouths and abundance of teeth, whale sharks and megamouth sharks are gentle filter-feeders. They eat tiny fish and plankton, making them safe and fascinating companions for divers.
21. Swell sharks can scare off predators by swallowing air or water, which doubles their body size. When they release it, they sometimes make a barking sound.
22. Sharks don’t have scales like other fish, but instead, their skin is covered in dermal denticles, which consist of small enamel-covered plates.
23. A shark's gestation period can last anywhere between two months and two years, depending on the species.
24. The megamouth shark wasn’t discovered until 1976, making it one of the newest shark species known to science.
25. Humans kill a huge number of sharks each year, an estimated 100 million globally, mostly due to fishing, shark finning, and bycatch in commercial fisheries. That’s an average of about 274,000 sharks every day. Far more than the number of people killed by shark attacks.
26. Globally, fewer than about 10 people die from shark attacks each year.
27. Great white sharks give birth to live young and offer no parental care after birth. Baby sharks head out to sea ready to feed and fend for themselves as soon as they are born.
28. Most fish have a single gill opening on each side of their bodies, while sharks have five to seven gill slits on each side.
29. Wobbegong sharks, also known as carpet sharks, are mostly nocturnal ambush predators that use their patterned bodies to blend into the ocean floor.
30. More people are killed each year by chairs and toasters than by sharks.
