Whale Shark Fact File
Credit: Under License
Wild 100 years
Captive 1 years
The World's Largest Fish!
The whale shark is recognized as the world's largest species of fish. They are among the largest animals of Earth only being beaten by the whales.
Despite their large size these animals pose little threat to other animals with only small teeth. They are primarily filter feeds which spend the year cruising the oceans to take advantage of plankton blooms, their main food source.
Little is known about their breeding behavior but it is suggested that females can produce up to 300 young in their life.
The species is threatened through bycatch in fisheries, tourism activities, vessel strikes and habitat pollution.
Read on to learn more about these fantastic fish.
What does the Whale Shark look like?
Across their body the whale shark is covered by blue-green skin. This is patterned with a range of white spots. Their pattern is highly variable and is unique to each individual. Along the body are a number of ridges.
They have three fins. Two dorsal fins, one on either side of the body and a single caudal fin which sits on the back.
The whale shark is the largest species of shark found in the world's oceans. They can reach lengths of up to 20m (66ft) which is on par with the length of a school bus. Their mouth is up to 1.5m (5ft) wide.
Males and females have a small external difference. The male has two appendages known as claspers on the belly which will function to channel sperm in to the female.
Their skeleton is formed from cartilage helping to make them light enough to float in the water.
An average weight for the whale shark is up to 12 tonne (13.2tons).
Despite the large size of the mouth they have small teeth and pose little threat to others.
How does the Whale Shark survive in its habitat?
These fish make use of suction to obtain their food. By raising their head above the surface and then sinking it will quickly draw water in to the mouth. This water contains plankton which is filtered by screening pads on the gill slits.
To clear the filter pads they will occasionally perform a small cough.
Food is detected using the nasal grooves which will sit above the mouth.
Often this species is seen with a number of smaller fish around them. It is thought that these help to provide protection.
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What does the Whale Shark eat?
The whale shark is a filter feeder. Their large mouth allows them to take in large amounts of water from which they can extract plankton.
On occasion they will also consume small fish and jellyfish. Groups gather at Christmas Island each year to feed on the larvae of the Christmas Island red crabs.
Learn more about the Whale Shark in this video from Free School on YouTube
Where do you find the Whale Shark?
Whale sharks are a wide ranging ocean going species. They range through almost all tropical oceans across the planet with the main exception being the Mediterranean Ocean.
Their range is restricted by temperature. The southernmost record of the species is from the coast of Victoria Australia and the northermost comes from the Bay of Fundy in Canada.
Where can the Whale Shark survive?
As a marine species the whale shark is found throughout tropical waters providing warm water in which they can live.
Credit: Under License
How does the Whale Shark produce its young?
Little is known about the breeding habits of the whale shark.
Inside the body of the female are around 300 eggs which are retained until they are ready to develop. She will gradually fertilize them following mating with a male.
The development of the young occurs inside a hard shell within her body. It has been hypothesized that the development of the hard shell is undertaken so the eggs can finish developing outside of the mother if needed.
In most cases though she will give birth to a large number of small young.
Sexual maturity is estimated to occur around 30 years old.
What does the Whale Shark do during its day?
Whale sharks are solitary for much of their life. Where plankton is in abundance small groups may form and feed together.
Throughout the year whale sharks undergo large migrations across the ocean. During these they only feed infrequently or not at all. Their migrations are timed to arrive during plankton blooms.
Breathing occurs through the gills located on either side of the head.
Credit: Under License
Predators and Threats
What stops the Whale Shark from surviving and thriving?
Adults have no predators except for man. Individuals often show scars from attacks by killer whales and sharks. It is thought that these may be able to prey on juveniles.
Populations of the whale shark are in decline. Two main populations are recognized. 75% of the total number of this species is found in the Indo-Pacific. This has suffered a 63% loss over 75 years.
The second population consisting of 25% of the total numbers for this species live in the Atlantic where they have suffered a 30% loss over 75 years.
A range of threats are facing the whale shark. These include bycatch within fisheries and in some areas direct fishing of the species themselves. Their association with fish increases this issue as they can be used to identify the location of fish species of interest and nets are then dropped close to them.
In many areas they are now protected under law and fishing has ceased.
Other issues which may affect them include boat strikes, pollution such as oil spills and inappropriate tourism activities with this species being popular for people to dive near.
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The whale shark is recognized as the world's largest species of fish.
Credit: Under License
Fish.wa.gov.au. 2022. [online] Available at: <http://www.fish.wa.gov.au/documents/recreational_fishing/fact_sheets/fact_sheet_whale_shark.pdf> [Accessed 25 February 2022].
Parksaustralia.gov.au. 2022. [online] Available at: <https://parksaustralia.gov.au/christmas/discover/nature/animals/whale-shark/> [Accessed 25 February 2022].
2011. FISHERIES FACT SHEET Whale Shark. [ebook] Government of Western Australia Department of Fisheries, pp.1-4. Available at: <http://www.fish.wa.gov.au/> [Accessed 25 February 2022].
Oceana. 2022. Whale Shark. [online] Available at: <https://oceana.org/marine-life/whale-shark/> [Accessed 25 February 2022].
Sharks World. 2022. Whale Shark. [online] Available at: <https://www.sharks-world.com/whale_shark/> [Accessed 25 February 2022].
Great Barrier Reef Foundation. 2022. Whale Shark – Great Barrier Reef Foundation. [online] Available at: <https://www.barrierreef.org/the-reef/animals/whale-shark> [Accessed 25 February 2022].
Encyclopedia Britannica. 2022. whale shark | Size, Diet, & Facts. [online] Available at: <https://www.britannica.com/animal/whale-shark> [Accessed 25 February 2022].
Australian Institute of Marine Science. 2022. Whale Sharks. [online] Available at: <https://www.aims.gov.au/species-at-risk/whale-sharks> [Accessed 25 February 2022].
Pierce, S.J. & Norman, B. 2016. Rhincodon typus. The IUCN Red List of Threatened Species 2016: e.T19488A2365291. https://dx.doi.org/10.2305/IUCN.UK.2016-1.RLTS.T19488A2365291.en. Accessed on 25 February 2022.