50 Fun Facts About Whale Shark

What distinction does the whale shark hold?

Largest living fish: only some whales are bigger, yet it lives on plankton, fish eggs and small schooling fish that it strains from the water.

Which animals have been filmed hunting whale sharks in the Gulf of California, flipping them onto their backs?

Orcas, a male nicknamed Moctezuma among them at three of the four recorded hunts, ram young whale sharks over and bite at the belly until they bleed out.

About how long was the largest whale shark ever reliably measured?

About 19 metres: a shark caught by India's Arabian Sea fishery came to 18.8 m. Sharks of 20 m have been claimed, but a 2015 review of ocean giants judged the 18.8 m figure the most reliable.

Despite its name, what kind of animal is the whale shark?

A cartilaginous fish: like every shark it has a skeleton of cartilage, not bone, and it breathes through gills, so unlike a whale it never has to come up for air.

The first whale shark known to science was harpooned in 1828 off which African port?

Cape Town: the shark was harpooned in Table Bay, and Andrew Smith, a British army surgeon who ran the town's new museum, wrote the first scientific description of the species.

How does a whale shark take in food when it hangs still and upright below the surface?

By sucking water in: it snaps its mouth open to gulp, then shuts it to force the water out through its gills, so it can feed on a dense patch of food without swimming at all.

Where is the whale shark's mouth positioned, unlike most sharks?

At the front of the head, where a mouth up to 1.5 metres across works like a scoop: the shark cruises along with it wide open.

What do whale sharks use their roughly 300 rows of teeth for?

No known purpose, researchers think: the teeth are tiny, and the shark feeds by straining small prey out of the water at its gills.

Which fish hitch rides on whale sharks, clinging on with a sucker on top of their heads?

Remoras hold on with a disc that is really a reshaped dorsal fin, saving the effort of swimming while they pick parasites and scraps off their host.

What armour did a 2020 study find covering the whale shark's eyeballs?

Tiny tooth-like scales, a form of the dermal denticles that cover a shark's skin, stud each eyeball. With no eyelids to shut, the shark can also pull its eyes about halfway back into their sockets.

Two mutations tune the whale shark's light-sensing eye pigment to which colour, the one that dominates the deep sea?

Blue light is what filters down to the depths. One of the two mutations causes night blindness in people, whose body heat makes the altered pigment fall apart; in the shark's eye it keeps working.

Which sex of whale shark grows larger, according to a 2020 Western Australian study?

Females: the study put them near 14.5 m on average against 8 to 9 m for males, which grow faster when young but level off much sooner.

Why do whale sharks linger at the surface after deep dives?

Warming back up, researchers think: the sharks are rarely found in water below 21 °C, and tags show that the colder the dive, the longer they stay on top afterwards.

A tagged whale shark, a surface feeder, once dived about how deep?

About 1,900 metres: the tag logged 1,928 m, well over a mile down, although sharks tracked in the open ocean spent about 95% of their time in the top 200 m.

Whale sharks from which waters are genetically distinct from all the rest?

The Atlantic holds about a quarter of the world's whale sharks, and because the two stocks are distinct the Red List scores them separately: down about 63% in the Indo-Pacific, over 30% in the Atlantic.

In 2009 over 400 whale sharks gathered off which coast, one of the largest gatherings ever?

The Yucatan, Mexico: one aerial survey counted 420 sharks packed into a patch of sea of about 18 square kilometres, all gorging on freshly spawned fish eggs.

Which Western Australian site hosts a famous seasonal whale shark aggregation?

Ningaloo's whale sharks arrive from March to feed on plankton blooming along the reef, close enough to shore that a licensed swim-with-the-sharks industry has grown up around them.

A 2020 study dated whale sharks' growth bands using carbon-14 left in their backbones by what?

Cold War atomic bomb tests spiked the carbon-14 in the sea, and the spike marks one band like a date stamp. It showed one band forms a year, not the two an earlier study assumed, so the sharks are twice as old.

Why are whale sharks so slow to recover from overfishing?

Decades to reach maturity: males are thought to be about 25 before they can breed, so a shark caught young has never bred at all.

A pregnant whale shark harpooned in 1995 was carrying roughly how many pups?

About 300 embryos, some still in egg cases and others already hatched, settled a long debate: the young hatch inside the mother and are born live.

How do female whale sharks seem to keep producing pups long after a single mating?

By storing sperm: DNA tests on embryos from one litter found a single father for them all, although they ranged from unhatched eggs to pups ready to be born.

A 38 cm whale shark found on a beach suggested the area is what?

A birthing ground, WWF suggested in 2009: the pup, found with its tail tied to a rope, was no bigger than the unborn embryos taken from a pregnant shark years earlier, so it may have been born close by.

Unlike most whale shark gatherings, those at Darwin Island in the Galápagos are nearly all what?

Adult females made up 91.5% of the sharks identified there in 2011 to 2013. Their swollen bellies were long read as pregnancy, until ultrasound scans published in 2023 found no embryos at all.

A whale shark tagged in 2007 swam over 7,000 km in 150 days, crossing which line?

The Equator: the tag surfaced just south of it, far out between Brazil and Africa, after at least 7,213 km. Researchers suspect the journey had to do with breeding.

Besides the whale shark, which two sharks are the only other filter feeders?

The basking and megamouth sharks: the megamouth went unseen until one was hauled up off Hawaii in 1976, so unlike anything known that a whole new family had to be created for it.

Whale sharks are technically omnivores because they ingest and partly digest what?

Sargassum seaweed drifts at the surface where the sharks feed, and chemical tests of their tissues suggest they draw real nourishment from it, which makes the whale shark the world's largest omnivore.

What is a whale shark doing when it 'coughs'?

Clearing its filter pads, it is thought: food is sieved from the water by 20 pads at the back of the mouth, and a sharp backflush clears whatever has built up on them.

Whale sharks sieve huge volumes of seawater, and a 2021 study found which pollutant in their droppings?

Microplastics: a juvenile sieves an estimated 21 kg of plankton a day, and floating plastic gathers in the same surface waters where the sharks feed.

Its numbers halved, the whale shark entered which IUCN category in 2016?

Endangered, one step up from Vulnerable: the sharks were still being fished in places and hauled up by boats chasing tuna, which often swim alongside them.

The whale shark is a carpet shark, which makes which of these sharks its close relative?

Nurse sharks are carpet sharks too, a group of mostly bottom-dwelling hunters, which makes the ocean-roaming whale shark the odd one out in its own order.

Whale shark meat was once sold as 'tofu shark' on which island, which banned the catch from 2008?

Taiwan's restaurants prized the delicate flesh that earned the tofu nickname, and fishermen there went on catching whale sharks for the table until the ban took effect.

Tags showing whale sharks sinking, probably dead, gave a 2022 study evidence of which hidden killer?

Ship strikes: whale sharks feed just under the surface, and the study found their routes overlap heavily with those of big merchant vessels and tankers in every major ocean.

At the tourist town of Oslob, how do fishermen keep wild whale sharks coming back every day?

By hand-feeding them: sharks learn to arrive within minutes of the feeder boats, and biologists worry that the handouts are changing how the animals behave, keeping them at the site for longer.

Which aquarium set the whale shark captivity record, over 26 years as of 2021?

Okinawa Churaumi has kept the same male since 1995. Most of its whale sharks were not hunted for display: the aquarium took in animals caught by accident in local fishermen's nets.

As of 2025, which is the only aquarium outside Asia ever to have kept whale sharks?

Georgia Aquarium, Atlanta, bought its sharks out of a commercial fishing quota, so animals that would otherwise have been eaten became the star exhibit the building was designed around.

How did the only whale sharks ever kept outside Asia reach their new aquarium?

In a cargo plane: a freighter fitted with a life-support system flew them 8,000 miles in water-filled tanks, and trucks carried them the last stretch.

What does the Malagasy name for the whale shark, 'marokintana', mean?

Many stars fits twice over: the name comes from the pale spots on the shark's back, and the software that tells one shark from another by those spots was adapted from a program astronomers use to match star fields.

The whale shark appears on the reverse of which country's 100-peso banknote?

The Philippines once hunted the shark it now prints on its money: it banned the catch in 1998, and towns such as Donsol now draw visitors to swim with the butanding, as it is called there.

In which country does the whale shark share its name, jinbei-zame, with a traditional summer outfit?

Japan's name for it is said to come from the jinbei's pattern. Fishermen also called it the Ebisu shark, after a god of good fortune: bonito shoal around it, so its arrival promised a big catch.

The whale shark, a green turtle and manta rays appear on the 1,000-rufiyaa banknote of which island nation?

The Maldives once had a whale shark fishery; it outlawed the catch, and snorkellers now come to swim with the young sharks that gather off South Ari Atoll.

Which Pixar film features Destiny, a near-sighted whale shark?

Finding Dory makes Destiny its heroine's childhood friend: the two grew up talking through the institute's pipes, and Destiny later helps Dory rescue her friends.

Whale sharks gather off which Australian island to feast on crab larvae?

Christmas Island's link was confirmed when DNA tests on a whale shark's droppings, scooped from the sea, showed it had been feasting on the larvae of the island's red crabs.

A 2021 study of injured whale sharks found signs that they may be able to regrow part of what?

A fin: photos taken five years apart showed the missing tip of one shark's dorsal fin grown back into its natural curve, and white spots were seen returning over healed wounds.

The first whale shark kept in captivity, in 1934, was held for about four months in what?

A netted-off sea bay on the Izu coast served as the pen. No aquarium tank held a whale shark until 1980, and the first sharks kept in tanks rarely lived long.

A cruising whale shark moves at about the speed of what?

A person walking: tracked sharks average only a few kilometres an hour, yet by keeping up that plod for months on end they cross whole ocean basins.

How do researchers measure the length of a whale shark as it swims past them?

With paired laser dots: two beams a fixed distance apart are shone on the shark's side, so every photo carries its own scale. Older guesses made against boats or knotted ropes could be well off.

Whale sharks were photographed swimming through thick oil from which disaster?

Deepwater Horizon's oil spread in 2010 over the area where a third of the northern Gulf's whale shark sightings had been made. The sharks could not avoid the surface slick, where they may feed for hours a day, though none was found dead.

In 2024 Thailand fined a diver for doing what to a whale shark?

Touching its tail: a video showed the diver reaching for the tip despite a warning not to touch marine life, and the company that took him out reported him to the national parks department.

Spanish names for the whale shark include 'pez dama', after which board game, whose grid its spots resemble?

Checkers, or draughts: pale spots sit in a grid of light stripes like the squares of a board, and because no two sharks share a pattern, researchers use it as each shark's name tag.

A 2014 report found hundreds of whale sharks a year being killed illegally for fins, skin and oil in which country?

China: investigators from a Hong Kong wildlife group spent three years undercover tracing the trade to a single factory, where they found a courtyard piled with giant fins.