Plankton and tiny fish get caught in the filters that line the whale shark’s throat. (123RF, R. Bishop)
Blue shows where whale sharks are found in the world’s oceans. (R. Bishop)
- The Whale Shark spends its life swimming through the open oceans in search of fish and squid. Unlike many other species of shark, the Whale Shark is known to feed on large shoals of tiny fish rather than hunting bigger fish and sea mammals. This makes the whale shark a filter feeder similar to whales and smaller sea animals.
- The whale shark is a filter feeder, one of only three known filter feeding shark species, the other two being the basking shark and the megamouth shark. It feeds on plankton, which includes copepods, krill, and fish eggs. The whale shark diet also consists of clouds of eggs during mass spawnings of fish and corals. The shark has many rows of vestigial teeth, which play no role in feeding. Instead, feeding occurs in two ways.
Baby Whale Shark Facts
What do Baby Sharks Eat? Baby sharks are called pups. Some shark species are born alive (ovoviviparous reproduction) while others are hatched from eggs (oviparous reproduction). But all shark pups are independent from the start. Shark pups are mostly found in swallow warmer waters and they will eat the same basic foods as large sharks but usually focus on smaller prey.
Whale sharks use active “ram” feeding (left), and still “suction” feeding (right). (R. Bishop)
Posted: April 30, 2018
Whale sharks are familiar, and yet mysterious. In many locations, boats take tourists out to view and swim with these giants. And yet experts are still baffled by things like exactly how they feed. Never fear, though. Scientists and researchers are on the case!
Here are some things scientists have learned:
1) Seawater is forced into the throat. Using photos, they measure the size of a whale shark’s wide open mouth. They calculate the amount of water that enters as the shark swims or as it sucks at the surface of the ocean.
2) Filter pads catch food. By experimenting with screening devices, people figure out what size plankton and tiny sea creatures will be captured on the ten pads that act like kitchen strainers lining the whale shark’s throat.
3) Food is probably pushed down toward the shark’s stomach as it piles up on the filter pads. Scientists often use their knowledge of other filter feeding sharks and whales to make educated guesses like this.
4) After passing through the (A) filter pads, water goes through (B) vents that direct the seawater over (C) gill membranes, which extract oxygen, and finally out of (D) gill slots on each side of the shark. Biologists can examine these organs carefully by dissecting a dead animal.
5) Several times an hour while feeding, whale sharks clear their clogged filter pads. People aboard small research boats can actually watch as sharks cough out clouds of food debris.
Want to Know:
Marine biologists ask: Do whale sharks really spend up to seven hours a day feeding and yet thrive on the amount of food energy in just a large McDonalds meal?
Fun to Know:
Baby sharks are called pups. And whale sharks are slow to grow up. They don’t start having pups until they are about 25 years old.
Male and female whale sharks — filter-feeding marine behemoths — grow at different rates, with females doing so more slowly but getting much larger than the guys, according to research that offers deeper insight into the biology of Earth's largest fish.
Researchers said on Wednesday they had tracked the growth of 54 whale sharks over a 10-year period in the vast Ningaloo Reef off Australia's west coast, where hundreds of these slow-swimming endangered fish migrate annually.
Whale sharks of both sexes were found to have their fastest growth as juveniles, about 20 to 30 centimetres annually.
Overall, males were found to grow slightly more quickly than females, plateauing at around 8 metres long after reaching sexual maturity at about 30 years old. Females plateaued at around 14 metres when they reached sexual maturity at about age 50.
It is believed whale sharks may live 100 to 150 years. The longest-known whale shark reached about 18 metres.
'Whale sharks are remarkable in that females have massive litters of pups, up to 300 at one time. Being very large is almost certainly a prerequisite for carrying this many young inside a female's body,' said Australian Institute of Marine Science marine biologist Mark Meekan, who led the research published the journal Frontiers in Marine Science.
These sharks have a brownish-grayish color on the back and sides with white spots, with a white underside.
'Our study provides the first evidence that male and female whale sharks grow at different rates,' Meekan said. 'Previously, researchers had to rely on estimates of growth and age extracted from the vertebrae of dead sharks that had either stranded on shore or been killed by a fishery. Samples were very limited and didn't cover a very wide size range of animals, confounding attempts to produce reliable estimates of growth patterns.'
Feed And Grow Fish Whale Shark
They are filter feeders, swimming great distances through the world's tropical oceans to find enough plankton to sustain themselves.
Shark And Whales Video
'Our study has important implications for conservation,' Meekan said. 'If it takes many years, 30 or more, for these animals to become mature, there are lots of threats such as hunting and ship-strike that they may succumb to before they get a chance to breed, making conservation strategies for these animals an urgent task.'