How Much Do You Know About the Deadliest Creatures in the Sea?


By: Isadora Teich

6 Min Quiz

Image: Shutterstock

About This Quiz

Have you stayed out of the water since "Jaws," or are you a denizen of the deep (or at least the part of the deep you can get to by wading out from shore)? In this quiz, we'll test your knowledge of the most dangerous creatures in the sea. Strap on your flippers and dive in!

Kids who grew up in the '70s and '80s remember Jacques Cousteau and his amazing underwater documentaries.  Camera in hand, he and his intrepid crew would dive deep, introducing us to some of the most amazing, colorful and often insanely dangerous sea creatures. These days, the schedule of the National Geographic channel and others are chock-full of shows about things in the sea that want to bite, crush, poison or otherwise maim you.

We all know about sharks, of course, thanks to Steven Spielberg's stirring nature documentary, "Jaws."  (Wait, that wasn't a documentary?) And of course you've heard of killer whales. You don't need to be a genius to realize they've got "killer" right in their name!  But how about a deadly jellyfish so small you can barely see it?  Or a fish that lives perfectly camouflaged with the sea floor that has a poison so deadly you'll never live to make it to the beach?

Now that you've given up ocean swimming for good, use your spare time to take our quiz on the ocean's deadliest creatures!

Do most kinds of sharks attack humans?

While sharks have a terrifying reputation, it is not exactly deserved. There are over 400 different kinds of sharks and only about 30 of those are known to attack humans.


Which of these creatures is more venomous in the sea than it is on land?

Sea snakes are typically hyper venomous, but nonaggressive and do not seek out human snacks. Their bites are typically small and often go unnoticed until they begin to cause deadly consequences. Organ and heart failure, vomiting, suffocation and paralysis are just a few of the nasty effects of a sea snake bite.


The bull shark is dangerous to humans because it:

Unique among sharks, the bull shark is notoriously aggressive and has been known to be found far inland, as it can swim in both salt and fresh water. Bull sharks have even been found in the Mississippi River.


Do Orcas hunt in groups?

Orcas often use strategy to hunt their prey, which is sometimes mother whales and their young. The Orca work together to separate calves from their mothers and keep them under water until they drown, so they can eat them.


Are hammerhead sharks likely to attack people?

Hammerhead sharks are large and highly predatory creatures with specialized detection abilities in their distinctive heads. However, hammerheads prefer to eat stingrays and not people.


What are polar bears?

Polar bears are the largest of terrestrial mammalian predators. Weighing up to 1,500 pounds, the massive arctic apex predators are exceptional swimmers and spend most of their life on ice or in the water.


Which kind of shark is responsible for the most unprovoked attacks on humans?

Great whites are infamous man-eaters, even though humans are not their preferred snack. These sharks are responsible for the most shark bites and most fatal attacks on humans of any shark species.


Which of these sharks is the fastest?

Mako sharks are the fastest swimmers among sharks. They can hit speeds of over 60 mph and are known to leap onto boats.


Which crocodile is considered the most dangerous to humans?

Saltwater crocodiles are known as Salties, but despite their cute nickname are hyper-aggressive apex predators known to take down sharks and humans easily. They are spread throughout India's eastern coast and Australia's northern coast, and most of Southeast Asia.


Are sharks older than dinosaurs?

In various forms, sharks have been hunting through the oceans for over 400 million years. They are the ocean's peak predators, and so skillful that they have hardly needed to evolve in the last 150 million years.


Which of these seals is a dangerous predator that even eats other seals?

Leopard seals are massive arctic predators that can reach up to 12 feet long and weigh 1,300 pounds. They are the only seals that eat warm-blooded prey, and one of the only seals to get particularly aggressive with or rarely attack humans.


What do bull sharks generally eat?

Bull sharks are large opportunistic hunters that are known to eat a wide range of animals. They even eat other sharks. These solitary apex predators can be found in both salt and fresh water.


Sharks range in size from 6 inches to __________ feet.

Dwarf lantern sharks are among the smallest in the ocean, at about 6 inches long. The massive whale shark can get as large as 60 feet. Neither of these sharks is known to attack humans.


Which of these whales is known to intentionally beach itself to catch prey?

Orca whales are massive and intelligent predators that can weigh 20,000 pounds and measure over 30 feet long. They use different tactics to catch prey, including intentionally beaching themselves in South America to catch sea lions and seals.


What makes a creature an apex predator?

Apex predators have no natural predators as healthy adults in the wild. They also capture live prey.


Saltwater crocodiles are the ________ reptiles on earth.

Saltwater crocs can grow to lengths of 22 feet or larger and have no natural predators. They can be found throughout Southeast Asia and parts of Africa, India, and Northern Australia.


Where do American alligators live?

American alligators inhabit freshwater wetlands from Texas to North Carolina. They are apex predators that will eat almost anything they come across.


Which creature can produce an electric discharge of up to 220 volts?

There are 69 species of electric ray, which can discharge between 8-220 volts. They are found in both shallow coastal waters and more than 3000 feet down in the ocean.


Great barracudas have ________ jaws.

Great barracudas are a common species of barracuda that are over 2 feet long when full-grown. Found in tropical and warm temperate waters, they have powerful jaws full of sharp fangs.


Do great white sharks do well in captivity?

While institutions have made numerous attempts to keep great white sharks in captivity over the years, in most cases this ended with the shark dying days or weeks in. Great whites are known to stop eating and bump into the walls in captivity.


Which eel can be as large as 13 feet long?

There are more than 200 species of Moray eels, but these frightening looking creatures are generally friendly. Most attacks occur when humans accidentally disrupt their burrows or try to hand feed them and the moray's poor eyesight causes them to take a finger or two by accident.


Is surviving a saltwater crocodile attack likely?

Saltwater crocodile attacks are often deadly, as these animals are strong, large, incredibly aggressive, and known to treat humans as prey. One or two fatal attacks occur every year in Australia. It is estimated that throughout Southeast Asia 20-30 attacks occur a year.


Which animal has the largest eyes of any ocean creature?

The colossal squid or Antarctic squid is the largest known invertebrate on earth. A specimen was once found with eyes that measured 11 inches in diameter.


What makes the giant Pacific octopus so dangerous?

The giant Pacific octopus is massive, the largest ever found weighing in at over 150 pounds. They are intelligent tricksters, known for recognizing individual people and wreaking havoc in the labs where scientists attempt to study them.


This species of jellyfish is terrifyingly massive, but has a relatively mild sting:

Lion's mane Jellyfish are massive animals that largely live in cold oceans. The largest one ever found had a bell over 7 feet long and tentacles over 121 feet long.


The Greenland shark is unique because of its:

The Greenland Shark has the longest known lifespan of any vertebrate on earth, possibly 400 years. They live deep in the ocean and their meat is toxic.


Which of these fish wreaked havoc on the Caribbean?

Lionfish are deadly predators with beautiful and deadly spines. In humans, their venom can cause agony, convulsion, numbness and vomiting. As an invasive species with no natural predators, they took a large toll on marine diversity in the Caribbean.


Which of these sea creatures is known to eat sharks?

Saltwater crocodiles enjoy a varied diet on land and sea. These massive largely Southeast Asian predators eat everything from buffaloes to tigers to sharks.


Which is the only animal known to ever attack great white sharks?

Killer whales are also known as Orcas. They are intelligent apex predators that often work together to attack prey.


Which massive predator is known for its taste for giant squid?

Sperm whales are the largest toothed predators on earth, and can reach over 60 feet in length. These massive creatures dive to the depths of the ocean where they hunt giant and colossal squids.


Which predator has the largest brain of any animal?

Sperm whales are some of the largest creatures in the ocean. They have the largest brains of any animal on earth, most of which is devoted to echolocation.


Which massive sea creature is known for cannibalism?

Giant squid are found in oceans across the globe and can grow to over 40 feet in length. Patterns of wounds and the stomach contents of giant squids which have washed ashore dead have led scientists to believe that they commonly attack and eat each other.


When was live giant squid evidence captured for the first time?

Japanese researchers took the first ever images of a live giant squid in 2004. Before that, most of what scientists knew about giant squid came from parts of their bodies which washed ashore after they died.


In which of these places are American crocodiles uncommon?

The American crocodile is found mostly in South and Middle America and the Caribbean. This large species has also been found in Florida.


Where can you find colossal squid?

The known range of this massive creature is north of Antarctica to the tips of South America, South Africa, and New Zealand. This animal shows deep-sea gigantism, and can be over 45 feet long and weigh over 1,600 pounds.


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