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What the sources say

Giant OarfishRegalecus glesne

Every figure, record and mechanism on the Giant Oarfish profile was written from a source, and this is the working table behind it: 46 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

Australian Museum 2021

Oarfish, Regalecus glesne. Australian Museum, 2021.

The page saysreliably documented to 8 meters
The source saysreliably documented to grow to 8 m in length
The page saysOpen ocean in tropical and temperate seas worldwide
The source saysThe Oarfish is found worldwide in all tropical and temperate marine waters.
The page saysreports of it eating other invertebrates and fish are yet to be validated
The source saysReports that the species feeds on invertebrates and fishes are yet to be validated.
The page saysThe giant oarfish has been reliably documented to 8 meters (26 feet)
The source saysIt has a ribbon-like body that has been reliably documented to grow to 8 m in lengthNote: 26 feet, converted from 8 m
The page saysFish up to 17 meters have been reported
The source saysspecimens up to 17 m in length have been reported
The page saysThe giant oarfish is found worldwide in tropical and temperate seas
The source saysThe Oarfish is found worldwide in all tropical and temperate marine waters.
The page saysIts confirmed diet is krill
The source saysAll verified cases of stomach contents consisted of krill (euphausiid shrimps).
The page saysReports of it also eating other invertebrates and fish have not been confirmed
The source saysReports that the species feeds on invertebrates and fishes are yet to be validated.
The page saysThe giant oarfish has been reliably documented to grow to 8 meters (26 feet) long, though specimens up to 17 meters (about 56 feet) have been reported
The source saysreliably documented to grow to 8 m in length, however specimens up to 17 m in length have been reportedNote: 26 feet and 56 feet converted from 8 m and 17 m

Source
02

Florida Museum of Natural History, Ichthyology 2025

Regalecus glesne (Oarfish). Florida Museum of Natural History, Ichthyology, 2025.

The page sayswith a red dorsal fin along its whole length
The source saysThe dorsal fin originates just above the relatively small eyes, running the entire length of the fish. It is distinctly colored, ranging from pinkish to cardinal red.Note: "red" for the source's "pinkish to cardinal red"
The page saysseen swimming upright in the open ocean
The source saysAn oceanic species ... It has also been observed swimming in a vertical position
The page saysmore typically down to about 200 meters, though reported as deep as 1,000 meters
The source saysAn oceanic species, the oarfish is found living at great depths to 3,280 feet (1,000 m) but more typically to depths of 656 feet (200 m).Note: "reported" is weaker than the source's "found" on purpose: five-2013 puts the deepest verified record at 463-492 m
The page saysKrill, strained from the water with specially evolved gill rakers
The source saysOarfish feed on plankton, crustaceans, and squid by straining them from the water column using specially evolved gill rakes located in the mouth. One specimen caught off the coast of California contained a large volume (10,000 individuals) of krill (euphausids).Note: krill is au-museum-oarfish's only verified stomach content, claimed below; gill "rakes" is the source's spelling of gill rakers
The page saysSwims with its body held straight by rippling a dorsal fin that runs its whole length
The source saysThe oarfish swims by undulating its long dorsal fin while its body remains straight ... The dorsal fin originates just above the relatively small eyes, running the entire length of the fish.
The page sayshas been seen swimming upright, which is believed to be how it searches for prey
The source saysIt has also been observed swimming in a vertical position in what is believed to be a method that the oarfish searches for prey items.
The page sayskeeps its long body straight and swims by rippling its red dorsal fin
The source saysThe oarfish swims by undulating its long dorsal fin while its body remains straight ... It is distinctly colored, ranging from pinkish to cardinal red.Note: "red" for the source's "pinkish to cardinal red"
The page saysan "amiiform" swimming style
The source sayswhich is knows as an amiiform mode of swimming
The page saysIt has also been seen swimming upright, which is believed to be how it searches for prey
The source saysIt has also been observed swimming in a vertical position in what is believed to be a method that the oarfish searches for prey items.
The page saysThat dorsal fin runs the entire length of its body in roughly 400 rays, with the first ten to twelve stretched into a trailing, spotted crest
The source saysThe dorsal fin originates just above the relatively small eyes, running the entire length of the fish ... Consisting of approximately 400 dorsal fin rays, the first 10-12 are elongated forming a trailing crest with reddish spots and flaps of skin on the tip of each ray.
The page saysthe Guinness Book of World Records considers it the longest bony fish alive in modern times
The source saysIt is considered the longest bony fish alive in modern times by the Guinness Book of World Records.
The page saysthough it is more commonly seen at about 3 meters (10 feet)
The source saysmore commonly observed at lengths of approximately 10 feet (300 cm) total lengthNote: 3 meters, converted from the source's 10 feet (300 cm)
The page saysThe maximum published weight for the species is 272 kilograms (600 pounds)
The source saysThe maximum published weight of this species is 600 pounds (272.0 kg).
The page saysmore typically down to about 200 meters, though it has been reported as deep as 1,000 meters
The source saysAn oceanic species, the oarfish is found living at great depths to 3,280 feet (1,000 m) but more typically to depths of 656 feet (200 m).Note: "reported" is weaker than the source's "found" on purpose, since five-2013 puts the deepest verified record at 463-492 m
The page saysIt has no visible teeth
The source saysOarfish have no visible teeth.
The page saysno swim bladder
The source saysThis species has no swim bladder.
The page saysinstead of scales its skin is coated in silvery guanine
The source saysThe body is scaleless with the skin covered instead by silvery guanine.
The page saysstrained from the water with specially evolved gill rakers
The source saysOarfish feed on plankton, crustaceans, and squid by straining them from the water column using specially evolved gill rakes located in the mouth.Note: gill "rakes" is the source's spelling of gill rakers
The page saysone fish caught off California contained 10,000 krill
The source saysOne specimen caught off the coast of California contained a large volume (10,000 individuals) of krill (euphausids).
The page saysIt is believed to live alone except when spawning
The source saysThis species is believed to live solitary lives with the exception of spawning activities.
The page saysA close relative, the streamer fish, has been reported to give a mild electric shock when handled, though it is unclear whether the giant oarfish can too
The source saysA close relative of the oarfish, the streamer fish (Agrostichthys parkeri) has been reported to be electrogenic, producing a mild shock when handled by humans. It is unclear if the oarfish shares this capability.
The page saysSharks and other large fish are its main potential predators, on account of its size
The source saysDue to its significant size, larger fish including sharks are the primary potential predators of the oarfish.
The page saysThe maximum published weight for the species is 272 kilograms (600 pounds). It is more commonly seen at about 3 meters (10 feet) long.
The source saysThe maximum reported length of the oarfish is 36 feet (1,100 cm) total length although it is more commonly observed at lengths of approximately 10 feet (300 cm) total length. ... The maximum published weight of this species is 600 pounds (272.0 kg).Note: 3 meters, converted from the source's 10 feet (300 cm)
The page saysThe giant oarfish keeps its body straight and swims by rippling its long dorsal fin, a style known as amiiform swimming. It has also been seen swimming upright, which is believed to be how it searches for prey.
The source saysThe oarfish swims by undulating its long dorsal fin while its body remains straight which is knows as an amiiform mode of swimming. It has also been observed swimming in a vertical position in what is believed to be a method that the oarfish searches for prey items.
The page saysa fish that swims without bending: its body stays straight while a dorsal fin running its whole length undulates
The source saysThe oarfish swims by undulating its long dorsal fin while its body remains straight ... The dorsal fin originates just above the relatively small eyes, running the entire length of the fish.Note: vibe.reason (task #211); replaces "majestic abyssal stillness", since the species typically lives above 200 m
The page saysit has been seen swimming upright
The source saysIt has also been observed swimming in a vertical positionNote: vibe.reason (task #211)

Source
03

McClain et al. 2015

McClain et al. (2015). Sizing ocean giants: patterns of intraspecific size variation in marine megafauna. PeerJ.

The page saysa detailed 2012 study found the largest museum specimens were just under 8 meters long, and no evidence that any oarfish grows longer
The source saysRoberts (2012) recent thorough description of Regalecus ... The largest specimens preserved in museum collections, of both R. russellii and R. glesne, are just under 8 m total length. I have not been able to find any evidence that Regalecus ever attain lengths greater than this.Note: "any oarfish" is the genus Regalecus, the source's scope
The page saysA report of a 15 to 16 meter oarfish stranded on Stronsay Island in the Orkneys in 1808 was based on the rotting carcass of a large basking shark
The source saysThe report of a 15–16 m (50–60 foot) long Regalecus stranded on Stronsay Island in the Orkneys in 1808 is based upon the rotting carcass of a large basking shark.
The page saysRecords of 10 to 11 meters added an estimated length for the missing tail end
The source saysRecords of oarfish 10, 10.7, or 11 m total length are based on addition of extrapolated lengths of the posterior part of the body lost at much smaller sizes.Note: "tail end" for "posterior part of the body"

Source
04

Benfield et al. 2013

Benfield et al. (2013). Five in situ observations of live oarfish Regalecus glesne (Regalecidae) by remotely operated vehicles in the oceanic waters of the northern Gulf of Mexico. Journal of Fish Biology.

The page saysUnderwater robots in the Gulf of Mexico spotted it at 463 to 492 meters, the deepest verified record of the species as of 2013
The source saysfive observations of apparently healthy oarfish Regalecus glesne by remotely operated vehicles are reported from the northern Gulf of Mexico. ... These observations include the deepest verified record of R. glesne (463-492 m)Note: "underwater robots" for remotely operated vehicles; 2013 is the paper's publication year, dating the record

Source
05

Albano et al. 2022

Albano et al. (2022). Distribution of the Order Lampriformes in the Mediterranean Sea with Notes on Their Biology, Morphology, and Taxonomy.

The page saysResearchers suggest that for long, thin fish like oarfish, an upright stance
The source saysmore elongated species such as the oar-ribbon fishes usually orientate their body verticallyNote: the review's scope is the elongate lampriforms, the oar-ribbon fishes among them; the mechanism is claimed separately below
The page saysan upright stance may help them spot prey against light filtering down from above while making their own outline harder to see
The source saysthe maintenance of a vertical position in the water column during predation, which was reported also for some Lampriformes species [ 7 , 8 ]. This feature may help these fish in the visualization of prey against downwelling light, and, at the same time, allow these elongate fish to minimize their appearanceNote: "downwelling light" paraphrased as "light filtering down from above"; "may help" kept as the source's hedge, with "Researchers suggest" for its attribution

Source
06

Orihara et al. 2019

Orihara et al. (2019). Is Japanese Folklore Concerning Deep‐Sea Fish Appearance a Real Precursor of Earthquakes? Bulletin of the Seismological Society of America.

The page saysIn Japan, folklore says an unusual appearance of a deep-sea fish such as an oarfish warns of a coming earthquake
The source saysIn Japan, folklore says that uncommon appearances of deep-sea fish are an earthquake precursor. ... fish species generally implicated in earthquakes, such as oarfish and slender ribbonfish, were the focus.
The page saysa statistical study built a database of newspaper and museum reports of these appearances, compared them against earthquake records, and found almost no link in place or time, calling the belief a superstition
The source saysHowever, a statistical survey has not been conducted on this subject because a database of such information had yet to be compiled. ... The authors constructed a database of reports from newspapers, academic articles, and the marine museum. ... the earthquake occurrence rate after deep-sea fish appearances can be evaluated. ... the spatiotemporal relationship between deep-sea fish appearances and earthquakes was hardly found. Hence, this Japanese folklore is deemed to be a superstition attributed to the illusory correlation between the two events.Note: "almost no link in place or time" for "the spatiotemporal relationship ... was hardly found"
The page saysJapanese folklore says an unusual appearance of a deep-sea fish such as an oarfish warns of a coming earthquake. A 2019 study built a database of newspaper, academic and museum reports of these appearances and compared them against earthquake records, finding almost no link in place or time between the two. The researchers concluded the belief is a superstition.
The source saysIn Japan, folklore says that uncommon appearances of deep-sea fish are an earthquake precursor. ... The authors constructed a database of reports from newspapers, academic articles, and the marine museum. ... the earthquake occurrence rate after deep-sea fish appearances can be evaluated. ... the spatiotemporal relationship between deep-sea fish appearances and earthquakes was hardly found. Hence, this Japanese folklore is deemed to be a superstition attributed to the illusory correlation between the two events.Note: 2019 is the paper's publication year (metadata), not text in the abstract itself

Source
07

Smith-Vaniz 2015

Smith-Vaniz (2015). Regalecus glesne. The IUCN Red List of Threatened Species 2015: e.T190378A115316206.

The page saysLeast Concern
The source saysIUCN Red List category: Least Concern (LC).

Source
08

Lozano-Cobo et al. 2021

Lozano-Cobo et al. (2021). Molecular Identification of Plerocercoids of Clistobothrium montaukensis (Cestoda: Phyllobothriidea) Parasitizing the King of Herrings Regalecus glesne. Acta Parasitologica.

The page saysFew parasites have been recorded in this fish, but scientists once pulled 63 tapeworm larvae from the intestine of an adult giant oarfish stranded in Mexico
The source saysthere are few records of parasites from either Regalecus species. We report plerocercoid larvae of phyllobothriidean cestodes parasitizing an adult R. glesne stranded in Bahía de La Paz, Baja California Sur, Mexico ... Sixty-three plerocercoids were obtained from the intestine of R. glesneNote: "63" appears as "Sixty-three" in the source; plerocercoids of cestodes are tapeworm larvae

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.