A whale shark swimming overhead. Learn more about whale shark facts here at downtoscuba.com. Image / Peach Snaps Photography
Can you spot the big spotty fish? Image / Peach Snaps Photography

Looking for a quick, easy-to-read fact guide to these ‘gentle giants?’ We have it all in our Ultimate Guide written by Anna Ortega, marine scientist extraordinaire, with whale shark facts that will amaze you and your dive buddies!

Gentle Giants

It never fails to shock me when massive ocean creatures sneak up on you, but they do without fail. 

The ocean has no doors, and your view of blue nothingness could turn into the outline of a slowly approaching, enormous 21-ton creature in mere seconds. This creature, the whale shark, will capture your attention instantly but barely notice you. It’s far more concerned with its next meal: the invisible plankton that live just below the surface.

Close up of a whale shark head and its unique spotted pattern.
These ‘gentle giants’ have a unique spotted pattern. Image / Adiprayogo Liemena

Whale sharks are known as “gentle giants” of the sea, because they are harmless to humans. They only eat things that are too tiny to see, and they’re slow swimmers who aren’t bothered by the curious eyes of humans, awestruck by their size and the unique constellation of patterns on their backs. There are many things about this mysterious animal that we don’t know yet, but researchers are working hard to understand more about this species and how to save it from extinction. 

Front profile of a whale shark's mouth
Open wide, and let’s delve into some cool whale shark facts. Image / Peach Snaps Photography

Allow me to catch you up to speed on what we do know about whale sharks facts: from how they got their name, to how you can help in their conservation.

What is a Whale Shark? 

Whale sharks (Rhincodon typus) are the largest fish alive today. They can grow to 12m (40ft) in length! These gentle giants spend time at the surface feeding on plankton but can dive to depths of over 1000m (3000 ft). Whale sharks have white undersides, but their back can be gray, blue, or brown and covered in white spots and stripes. These patterns are unique to each individual and can be used to identify different individuals.

Whale Shark Facts

A whale shark swimming over coral.
The ‘gentle giants’ of the sea. Image / Peach Snaps Photography

Why is a whale shark called a “whale shark”?

The largest fish on the planet, whale sharks, are sharks and not whales. But because they can grow to be so big (up to 12m / 40 ft, and 21 tons / 42,000 lbs), they earned the title of “whale” as well. 

Is a whale shark a shark? 

Whale sharks are sharks. A shark is a type of fish that has cartilage instead of bones. What’s the difference? In humans, our skeleton is hard bone, but our ears are made of cartilage. 

The first whale shark specimen recorded in science history was discovered off the coast of South Africa, and Dr. Andrew Smith described it as “the largest living shark in the ocean”.

Is a whale shark a whale? 

The whale shark is given the title “whale” for its size, but it is not a whale. Real whales are mammals: they need to breathe air, they are warm blooded, and they produce milk for their young. Whale sharks and other fish do not do any of those things. Whale sharks are cold-blooded, extract oxygen from the water with their gills, and their babies have to filter-feed to eat, just like the adults.

Is a whale shark a mammal? 

Whale sharks are not mammals, they are fish. Mammals are warm-blooded, have hair or fur, breathe with lungs, and give birth to live young. On the other hand, fish are cold-blooded, have scales, breathe with gills, and hatch from eggs. Fish and mammals are both vertebrates, which means they have a backbone. To make it even more confusing, whale sharks (and other sharks) don’t have a backbone made of bone, but one of cartilage.

Underbelly of a whale shark swimming overhead.
The whale shark has unique spots on top, with a white underbelly. Remoras love to hitch a ride with this giant fish. Image / Peach Snaps Photography

Whale Shark Personality

Whale sharks are known as “gentle giants”. They are calm creatures who spend most of their time in the open ocean, alone, and they like it that way. They do share feeding grounds, and many whale sharks will converge to eat if there is a plankton bloom. Whale sharks are slow swimmers, and there has never been a report of a whale shark injuring a person.

Whale sharks are often seen at popular dive sites, whether to take advantage of the plankton, or to check out a diver’s bubbles. It’s been observed that whale sharks enjoy the bubbles exhaled by scuba divers and are quite content with swimming around a boat and people.

A whale shark enjoying the bubbles from scuba divers.
A whale shark seeking out the bubbles made by scuba divers. Image / Peach Snaps Photography

You will often see remora fish hitching a ride with a whale shark, to collect any scraps of food dropped by the whale shark. This is an indication of how chilled out a whale shark can be! 

How much does a whale shark weigh? 

Whale sharks begin as babies that weigh less than a kilogram (2 lbs) but could grow into adults that weigh 21 tons (42,000 pounds)! That’s a little less than two African bush elephants, and a little more than two school buses.

Baby whale sharks

Most sharks give birth to a few, large babies. Whale sharks, though, give birth to hundreds of very small babies, called pups. Whale sharks can grow to 12m (40ft) but give birth to babies that are only 45cm (20 inches)! Because they are so small in such a big ocean, they’re extremely hard to find and study. Most of what we know about baby whale sharks comes from a study of one fisheries who caught a pregnant whale shark in 1996. The pregnant whale shark in the study was hunted, but was bought and given to scientists, who were able to use it to understand even more about the elusive whale shark and its pups.

What do whale sharks eat? 

Whale sharks are carnivores. Judging by their size, you might think they eat large fish or even other sharks, but they can’t – they’re filter feeders. Filter feeding is when an animal opens its jaws, swims forward, and passively collects all the tiny things in its path. Whale sharks swim along the surface with a gaping mouth, scooping up plankton: microscopic plants and animals, and sometimes tiny fish.

Whale sharks are filter-feeders
Whale sharks are filter-feeders. The remoras are hoping for some leftovers. Image / Peach Snaps Photography

Do whale sharks have gills? 

Whale sharks do have gills; five on each side of their body. They are fish, so they use their gills to breathe by getting oxygen from the water as they swim. Not only do whale sharks use their gills for breathing, but they use them to filter feed. Their gills are able to catch small plankton and animals, and the water is expelled out through their gill slits.

Why do whale sharks come to the surface if they don’t breathe air? 

It’s true that whale sharks breathe underwater, but they eat plankton. Plankton (microscopic plants and animals) live at the surface of the ocean, where they can get sunlight to make food like land plants. This means that whale sharks often come to the surface to feed on plankton in sunny, nutrient-rich places. This works out well for those of us that want to swim with whale sharks!

A whale shark swimming under a dive boat.
Whale sharks are curious creatures. Image / Peach Snaps Photography

Where to see a whale shark

You can find a whale shark near tropical waters across the world. They migrate to find food, and this means that some places become seasonal whale shark hotspots: Mexico, the Ningaloo Reef in Western Australia, The Similan Islands, Thailand, Donsol in the Philippines, Indonesia, and Tanzania.

Is it safe to swim with whale sharks? 

Whale sharks do not pose any threats to humans, and there has never been any record of a whale shark injuring or killing a human. Whale sharks are docile creatures, which makes their feeding ground “hotspots” excellent places for people who want to experience these gentle giants up close.

Check out: Diving in Koh Tao, Thailand; A hotspot for visiting whale sharks!

Down to Scuba founder, Emma, swimming with a whale shark.
DTS founder, Emma, swimming with a whale shark in Koh Tao, Thailand. Image / Peach Snaps Photography

Swimming with whale sharks

The ocean is huge, and its creatures are free to go anywhere. That means that while it’s never a perfect guarantee that you can see a whale shark, we do know that whale sharks migrate to follow their food. They eat plankton, and environmental conditions mean that there will be plankton blooms in certain places at certain times of the year.

Because of this, there’s a good chance you can see these majestic creatures from June to November in the Galapagos, in Mexico from the summer (Isla Mujeres, Bahia de Los Angeles) to October (La Paz) to November and December (Socorro Island). And in Oslob, The Philippines, local fishermen have been authorized to feed the whale sharks. The fishermen do feed the whale sharks almost every day, which means that whale sharks can be seen regularly, year-round.

Experienced snorkeler in advanced conditions
Swimming with whale sharks. Photo by Michael Liao on Unsplash

What hunts whale sharks?

Adult whale sharks are so big that most have no natural predators, but old or sick whale sharks are easy prey for killer whales. Sharks and big fish, such as blue marlins, have been known to eat juvenile whale sharks, since the pups (babies) are so small. Lastly, humans hunt whale sharks in some parts of the world. 

Are whale sharks endangered? 

Yes. Unfortunately, whale shark facts state that whale sharks are classified as “Endangered” by the IUCN. Why? Whale sharks may get caught accidentally in fishing gear, or caught on purpose for their fins. Whale shark meat and fins are eaten as a delicacy in some parts of Asia.

The warming climate is also affecting their ocean home, and plastic pollution is dangerous for these filter feeders. Fortunately, whale sharks are protected internationally from hunting and trade by CITES (the Convention in International Trade in Endangered Species of Flora and Fauna). Many countries have enforced national regulations to protect whale sharks from fishing, and many conservation groups focus on whale sharks.

A whale shark swimming around.
Whale sharks are endangered. Image / Peach Snaps Photography

Whale Shark Conservation Projects

There are many whale shark conservation projects around the globe. These organizations work hard to minimize whale shark hunting by studying whale sharks and raising public awareness about why whale sharks are important. One wonderfully successful example of this is the Whale Shark Conservation Project, led by the Wildlife Trust of India.

In the 1990s along the Indian state Gujarat, whale sharks were commonly hunted. To stop this, the species was added to India’s Wildlife Protection Act in 2001, and in 2004, the Whale Shark Campaign was launched. This project was started by the Wildlife Trust of India with a goal to spread information to the coastal communities of Gujarat about whale sharks, their decline, and their new protected status. The Wildlife Trust of India encouraged the fishermen to become protectors of whale sharks, and they succeeded. The perception of whale sharks and the local community attitude toward them completely changed.

How to adopt a whale shark

As a way to fund their scientific research, many whale shark conservation projects offer an interesting way to get involved: by adopting a whale shark. You don’t get to take it home, but you do get to name it and, in some cases, track it. Although, the organizations that offer these adoptions (to name a few: World Wildlife Fund, Wildbook, MarAlliance) make it clear that because whale sharks are wild, they can’t guarantee that you’ll be able to track your shark forever. If your shark is spotted, tracked, or photographed, they’ll do their best to get that information to you.

Your donation, which gives you the naming and/or tracking rights of a whale shark, goes directly towards funding whale shark research. Some of these projects include identifying whale sharks by photos of their spot patterns, tagging whale sharks to track their movement, work to study whale sharks in the field, contribute to scientific equipment upkeep, and help pay the people that so work on these projects to save and understand whale sharks.

These whale shark facts have taught you a lot about whale sharks, but there is still a lot that scientists don’t know about them. By learning more yourself and supporting whale shark research and conservation work, you play a part in saving these majestic “gentle giants”.

Wide shot of a whale shark in the ocean.
Learn how to protect and conserve these amazing creatures. Image / Peach Snaps Photography

To learn more about marine life written by Anna Ortega, check out her guide on eagle rays. You can also read our exclusive interview with UW photographer, Paddy from Peach Snaps Photography, and learn some tips on how to get your own perfect photo of a whale shark!

Anna grew up far away from the ocean, but that hasn’t stopped her passion for marine science. She is a marine biology graduate student at the University of Western Australia, spends her summers as a marine educator in the Caribbean, and studied spotted eagle ray behavior in the Meso-American reef.