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What the sources say

Whale SharkRhincodon typus

Every figure, record and mechanism on the Whale Shark profile was written from a source, and this is the working table behind it: 66 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Animal Diversity Web, University of Michigan

Rhincodon typus (whale shark). Animal Diversity Web, University of Michigan.

The page saystooth-like scales
The source saysThe skin is studded with dermal denticles, which are tooth-like scale structures
The page saysWarm tropical and subtropical oceans worldwide
The source saysWhale sharks are a highly migratory, pelagic species distributed throughout the world's tropical seas ... They are known to inhabit both deep and shallow coastal waters of subtropical zones
The page saysA whale shark's skin is studded with dermal denticles, tooth-like scales
The source saysThe skin is studded with dermal denticles, which are tooth-like scale structures
The page saysA whale shark's pattern of light spots and stripes stays the same for life
The source sayscomposed of light spots and stripes over a dark body ... Coloration remains the same over the shark's lifespan, making it an ideal character for photo identification of individuals.

Source
02

Georgia Aquarium

Whale Shark. Georgia Aquarium.

The page saysWorld's largest fish
The source saysThe largest fish in the world
The page saysthat filters its food out of seawater
The source saysFilters food from the water by “cross-flow filtration,”
The page saysusually offshore
The source saysHabitat Typically found offshore
The page saysfrequents coastal upwelling areas and sometimes enters lagoons and coral atolls
The source sayssometimes entering lagoons or coral atolls. Frequents shallow water areas near bays and upwelling coastal areas near continental drop-offs
The page saysZooplankton, including sergestid shrimps and fish eggs, plus krill, jellies, copepods, coral spawn, and small fishes such as sardines and anchovies
The source saysConsists of zooplankton, specifically sergestid shrimps and fish eggs, as well as krill, jellies, copepods, coral spawn, etc. and small fishes (sardines, anchovies, etc.)
The page saysThe whale shark (Rhincodon typus) is the largest fish alive.
The source saysThe largest fish in the worldNote: a record, so it cites the current institution page; Ong et al. 2020 and Yamaguchi et al. 2023 say the same
The page saysA current aquarium profile gives its common length as 18 to 32.8 feet (5.5 to 10 meters)
The source saysCommon length is between 18 and 32.8 feet (5.5 – 10 m).
The page saysthe largest measured at 61.7 feet (18.8 meters)
The source saysThe largest measured whale shark was 61.7 feet (18.8 m).Note: the current institution page; ADW's older account gives 20 m (high) and Ong et al. 2020 'up to 18 m'
The page saysIt adds that a living whale shark is "very difficult to weigh accurately."
The source saysin life, it is very difficult to weigh accurately
The page saysA whale shark's teeth are tiny, point backward and are thought to play no role in feeding, though there are about 300 rows of them lining the inside of each jaw.
The source saysTeeth are tiny and pointed backward; thought to have no function in feeding. ... There are about 300 rows of tiny teeth along the inner surface of each jaw, just inside the mouth.
The page saysa mouth up to four feet wide
The source sayscan reach up to 4ft wide
The page sayswater drains out through the gills while plankton, which carries more momentum, keeps moving toward the back of the mouth
The source saysRather, water is directed away through the gills while particles (which have more momentum) carry on towards the back of the mouth
The page saysTheir threats include entanglement in fishing nets and boat strikes
The source saysSpecific threats to whale sharks include entanglement in fishing nets, boat strikes, ingestion of marine debris and micro plastics
The page saysno two sharks' spot patterns are exactly alike, so researchers use them like fingerprints
The source saysIndividual spot patterns, like human fingerprints, no two are exactly alike.

Source
03

Pierce et al. 2025

Pierce et al. (2025). Rhincodon typus. The IUCN Red List of Threatened Species 2025: e.T19488A126673248.

The page saysEndangered
The source saysIUCN Red List category: Endangered (EN).Note: stats.conservationStatus
The page saysWhale sharks are now listed as Endangered on the IUCN Red List.
The source saysIUCN Red List category: Endangered (EN).

Source
04

Ong et al. 2020

Ong et al. (2020). Annual Bands in Vertebrae Validated by Bomb Radiocarbon Assays Provide Estimates of Age and Growth of Whale Sharks. Frontiers in Marine Science.

The page saysOne 10-meter female, whose vertebrae were studied for a 2020 aging paper, had an estimated weight of about 7,000 kilograms (15,400 pounds).
The source saysA 10 m total length (TL) female with an estimated weight of 7000 kg was landed in Karachi, Pakistan in February 2012.Note: paper published 2020 (Front. Mar. Sci., 06 April 2020); 7,000 kg x 2.2046 = 15,432 lb, given as about 15,400 lb
The page saysIts authors counted growth bands in the vertebrae of 20 sharks
The source saysCounts of growth bands in 20 sharks ranged from 15 to 50
The page saysused carbon-14 from 1950s and 60s nuclear bomb tests
The source saysAbove-ground testing of thermonuclear weapons in the 1950s and 60s increased the ratio of carbon 14 isotopes in the atmosphere that were then mixed into the ocean, passed up food webs and incorporated into marine organisms
The page saysto confirm that each band marks a year, and estimated ages of up to 50 years
The source saysHere, we provide the first validation of the annual formation of growth bands within the vertebrae of the whale shark using bomb radiocarbon assays. Ages of up to 50 years were estimated from sectioned vertebrae
The page saysThe bands narrowed in the oldest sharks
The source saysBand width decreased with age, narrowing substantially in the oldest individuals
The page saysbut had not stopped forming
The source saysThere was no cessation of the formation of growth bands in the vertebrae of older sharksNote: the oldest sharks are among the 'older sharks' the quote covers
The page saysScientists estimate a whale shark's age by counting growth bands in its vertebrae.
The source saysthe first validation of the annual formation of growth bands within the vertebrae of the whale shark using bomb radiocarbon assays. Ages of up to 50 years were estimated from sectioned vertebrae
The page saysA 2020 study confirmed that each band marks one year
The source saysHere, we provide the first validation of the annual formation of growth bands within the vertebrae of the whale shark using bomb radiocarbon assays.Note: study published 2020 (Frontiers in Marine Science)
The page saysby measuring radiocarbon from 1950s and 60s nuclear bomb tests inside the vertebrae
The source saysAbove-ground testing of thermonuclear weapons in the 1950s and 60s increased the ratio of carbon 14 isotopes in the atmosphere that were then mixed into the ocean, passed up food webs and incorporated into marine organisms. As a result, the timing of the deposition of bands can be validated by comparing carbon isotope values within vertebrae
The page sayscomparing it with a reference record from fish ear stones of known age
The source sayswe used a reference chronology developed from young known-age otolithsNote: otoliths are fish ear stones
The page saysIt estimated ages of up to 50 years, and the older sharks were still forming new bands.
The source saysAges of up to 50 years were estimated from sectioned vertebrae ... There was no cessation of the formation of growth bands in the vertebrae of older sharks

Source
05

Motta et al. 2010

Motta et al. (2010). Feeding anatomy, filter-feeding rate, and diet of whale sharks Rhincodon typus during surface ram filter feeding off the Yucatan Peninsula, Mexico. Zoology.

The page says20 filter pads that strain more than 600,000 liters of seawater an hour in a 6-meter shark, by one estimate
The source saysThe filtering apparatus is composed of 20 unique filtering pads ... it was estimated that a whale shark of 443 cm total length (TL) filters 326 m(3)/h, and a 622 cm TL shark 614 m(3)/hNote: 614 m3/h = 614,000 L/h, so 'more than 600,000 liters'; 622 cm = 6.22 m, given as '6-meter'
The page saysthrough 20 filter pads meshed with holes averaging just 1.2 millimeters across
The source sayscomposed of 20 unique filtering pads ... with openings averaging 1.2mm in diameter
The page saysCross-flow filtration helps keep that mesh from clogging
The source saysA feeding mechanism utilizing cross-flow filtration of plankton is described, allowing the sharks to ingest plankton that is smaller than the mesh while reducing clogging of the filtering apparatus.
The page saysOff Mexico's Yucatan Peninsula, researchers estimated that a shark about 6 meters long filters more than 600,000 liters of seawater an hour while ram feeding at the surface.
The source saysstudied off Cabo Catoche, Yucatan Peninsula, Mexico. ... During surface ram filter feeding ... it was estimated that a whale shark of 443 cm total length (TL) filters 326 m(3)/h, and a 622 cm TL shark 614 m(3)/hNote: 622 cm = 6.22 m, 'about 6 meters'; 614 m3/h = 614,000 L/h, so 'more than 600,000 liters'
The page saysThrough cross-flow filtration.
The source saysA feeding mechanism utilizing cross-flow filtration of plankton is described
The page saysWater flows into its mouth, through 20 filter pads meshed with holes averaging just 1.2 millimeters wide, and across the gills.
The source saysThe filtering apparatus is composed of 20 unique filtering pads that completely occlude the pharyngeal cavity. A reticulated mesh lies on the proximal surface of the pads, with openings averaging 1.2mm in diameter. Superficial to this, a series of primary and secondary cartilaginous vanes support the pads and direct the water across the primary gill filaments.
The page saysA 2010 study described how this lets the shark swallow plankton smaller than the mesh while reducing clogging.
The source saysA feeding mechanism utilizing cross-flow filtration of plankton is described, allowing the sharks to ingest plankton that is smaller than the mesh while reducing clogging of the filtering apparatus.Note: study published 2010 (Zoology); 'allowing' given as 'lets'
The page saysIts authors estimated that a whale shark about 6 meters long, ram feeding at the surface off Mexico's Yucatan Peninsula, filters more than 600,000 liters of seawater an hour, and that the sharks there spent about 7.5 hours a day feeding on average.
The source saysstudied off Cabo Catoche, Yucatan Peninsula, Mexico. ... During surface ram filter feeding ... Sharks on average spent approximately 7.5h/day feeding at the surface ... a 622 cm TL shark 614 m(3)/hNote: 622 cm = 6.22 m, 'about 6 meters'; 614 m3/h = 614,000 L/h, so 'more than 600,000 liters'
The page saysoff Mexico's Yucatan, feeds by cruising at about 1.1 meters per second with its mouth open at the surface
The source saysDuring surface ram filter feeding, sharks swam at an average velocity of 1.1m/s with 85% of the open mouth below the water's surface.Note: vibe.reason; replaces 'tranquil ocean drift', a mood (#180). Yucatan scope as in the title and the body
The page saysfor around 7.5 hours a day
The source saysSharks on average spent approximately 7.5h/day feeding at the surfaceNote: vibe.reason; same figure as the FAQ

Source
06

Tomita et al. 2020

Tomita et al. (2020). Armored eyes of the whale shark. PLOS ONE.

The page saysarmored in tooth-like scales down to its eyeballs
The source saysincluding the discovery that they are covered with dermal denticles, which is a novel mechanism of eye protection in vertebrates
The page saysDermal denticles that armor its eyeballs
The source saysincluding the discovery that they are covered with dermal denticles, which is a novel mechanism of eye protection in vertebrates
The page saysthat also cover its eyes
The source saysincluding the discovery that they are covered with dermal denticles
The page saysA 2020 study counted about 2,900 of these eye denticles around the iris of one shark's eye
The source saysNumerous dermal denticles are distributed on the eye surface around the iris ... the total number of eye denticles was ca. 2900 in OCF-P04248Note: study published 2020 (PLOS ONE); OCF-P04248 is one eyeball taken from a dead bycatch shark
The page saysshaped differently from the denticles on the rest of the body in a way consistent with resisting abrasion
The source saysThe eye denticle differs in morphology from that of the dermal denticles distributed over the rest of the body, consistent with a different function (abrasion resistance)
The page saysobserved three captive whale sharks
The source saysEye retraction behavior was observed in all whale sharks (specimens A–C) examined in this studyNote: specimens A-C are three; A and B lived in an exhibition tank at Okinawa Churaumi Aquarium and C in an open-water fish pen beside it
The page sayspull their eyes back into their sockets in under a second when a diver approached, by up to about half the eyeball's diameter
The source saysWhen an object approached (in this case the diver), the eyes were retracted into the orbit with a duration (from the onset of eye retraction to complete retraction) of less than 1 s. Ultrasound data showed that the maximum retraction distance was 3.3 and 2.8 cm (50.4 and 49.8% of the eyeball diameter)
The page saysThe authors knew of no other shark or ray with denticles on its eyes.
The source saysAs far as we know, eye denticles have not been found in other elasmobranchs, including species closely related to the whale sharkNote: elasmobranchs are sharks and rays
The page saysWhale sharks have no eyelids, so the surface of the eye is less protected than the rest of the body, which is covered in dermal denticles.
The source saysConsidering that these tissues are exposed and that whale sharks lack eyelids; the eye surface is less protected from mechanical damage than other regions of the body that are covered with mineralized dermal denticles.
The page saysA 2020 study found denticles on the eyes too, about 2,900 of them around the iris of one shark's eye
The source saysNumerous dermal denticles are distributed on the eye surface around the iris ... the total number of eye denticles was ca. 2900 in OCF-P04248Note: study published 2020 (PLOS ONE); FAQ 1 restatement of the body's count
The page saysshaped differently from the ones on the rest of the body in a way consistent with resisting abrasion
The source saysThe eye denticle differs in morphology from that of the dermal denticles distributed over the rest of the body, consistent with a different function (abrasion resistance)
The page saysThe authors say they are probably useful in reducing the risk of damage to the eye's surface.
The source saysthe covering of the eye surface with denticles in the whale shark is probably useful in reducing the risk of mechanical damage to the eye surface
The page saysThe same study observed three captive whale sharks pull their eyes back into their sockets in under a second when a diver approached, by up to about half the eyeball's diameter.
The source saysWhen an object approached (in this case the diver), the eyes were retracted into the orbit with a duration (from the onset of eye retraction to complete retraction) of less than 1 s. Ultrasound data showed that the maximum retraction distance was 3.3 and 2.8 cm (50.4 and 49.8% of the eyeball diameter)Note: specimens A-C, captive at or beside Okinawa Churaumi Aquarium (see the body claim)

Source
07

Womersley et al. 2021

Womersley et al. (2021). Wound-healing capabilities of whale sharks (Rhincodon typus) and implications for conservation management. Conservation Physiology.

The page saysResearchers following injured whale sharks in photographs from two Indian Ocean aggregation sites
The source saysThe present study makes use of a unique and valuable photographic data source from two whale shark aggregation sites in the Indian Ocean.
The page saysestimated that the wounds reached 90 percent closure by about day 35 overall, 22 days for scrapes and 50 for cuts
The source saysAll wounds reached a point of 90% surface area closure by Day 35. There were differences in healing rate based on wound type, with lacerations and abrasions taking 50 and 22 days to reach 90% healing, respectively.Note: the 35 days is the x-intercept (34.84 days) of an exponential model fitted to all wounds (Fig. 9), so 'estimated ... overall'; lacerations are cuts, abrasions scrapes
The page saysOne juvenile male, first seen in 2006 missing the tip of his first dorsal fin, appeared about five years later to have regrown it
The source saysa juvenile male from the Djibouti aggregation was sighted in 2006 missing the tip of the first dorsal fin. When this individual was re-sighted approximately 5 years later (2011) it appeared to have re-grown the previously amputated first dorsal fin tip
The page sayswhich the authors called the first reported case of a shark or ray regrowing part of an appendage
The source saysThis is the first reported case of an elasmobranch re-growing a part of an appendageNote: elasmobranchs are sharks and rays

Source
08

Brunnschweiler et al. 2009

Brunnschweiler et al. (2009). Deep-diving behaviour of a whale shark Rhincodon typus during long-distance movement in the western Indian Ocean. Journal of Fish Biology.

The page saysOne tagged off Mozambique dove to 1,286 meters, deep into the mesopelagic and bathypelagic zones, while covering at least 1,200 kilometers of ocean in 87 days.
The source saysa minimum distance of 1200 km in 87 days. Dives to depths well into the mesopelagic and bathypelagic zones (1286 m maximum depth) were recorded

Source
09

Yamaguchi et al. 2023

Yamaguchi et al. (2023). Whale shark rhodopsin adapted to deep-sea lifestyle by a substitution associated with human disease. Proceedings of the National Academy of Sciences.

The page saysWhale sharks also dive far below the surface.
The source saysThe whale shark, which dives into the deep sea of nearly 2,000 meters besides near-surface filter feeding
The page saysThe whale shark's eye pigment, rhodopsin, absorbs light best at 478 nanometers
The source saysuncovered a remarkable shift of the wavelength of the maximum absorbance (λmax) to 478 nmNote: RHO is rhodopsin
The page saysclose to the light of about 480 nanometers that fades least in the deep sea
The source saysthe light of approximately 480 nm is the least attenuated in the deep seaNote: 'fades least' for 'least attenuated'
The page saysA 2023 study traced that tuning mostly to one spot in the pigment, site 94
The source saysour spectroscopy of recombinant whale shark RHO mutants revealed that this blue shift is caused dominantly by an unprecedented spectral tuning site 94Note: study published 2023 (PNAS); 'caused dominantly' given as 'mostly'; the blue shift itself was 'previously shown', so the 2023 finding is its cause
The page saysthe same site where, in humans, a mutation causes a form of night blindness
The source saysIn humans, the mutation at the site causes congenital stationary night blindness (CSNB) by reducing the thermal stability of RHO

Source
10

Arzoumanian, Holmberg & Norman 2005

Arzoumanian, Holmberg & Norman (2005). An astronomical pattern-matching algorithm for computer-aided identification of whale sharks Rhincodon typus. Journal of Applied Ecology.

The page saysA 2005 study adapted a computer algorithm originally built for comparing star patterns in pictures of the night sky to match photos of whale shark spots.
The source saysspot patterns captured in photographs of whale shark flanks have been used, in the past, to make identifications by eye. We have automated this process by adapting a computer algorithm originally developed in astronomy for the comparison of star patterns in images of the night sky.Note: paper published 2005 (Journal of Applied Ecology)
The page saysTested on pictures of sharks that had already been identified, it matched the correct pairs more than 90 percent of the time.
The source saysIn tests using a set of previously identified shark images, our method correctly matched pairs exhibiting the same pattern in more than 90% of cases.

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.