AnimalTracks.wiki

What the sources say

Japanese Giant SalamanderAndrias japonicus

Every figure, record and mechanism on the Japanese Giant Salamander profile was written from a source, and this is the working table behind it: 70 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.

Profile updated

Source
01

Smithsonian's National Zoo and Conservation Biology Institute

Japanese giant salamander. Smithsonian's National Zoo and Conservation Biology Institute.

The page saysUp to five feet of living river boulder
The source saysreaching lengths of up to 5 feet (1.5 meters)Note: tagline; 'living river boulder' is a metaphor
The page saysbreathes through its skin
The source saysJapanese giant salamanders "breathe" primarily through their skinNote: tagline
The page sayshunts by smell and vibration
The source saysthey rely on smell and vibrations in the water when huntingNote: tagline
The page saysgives off a peppery smell when stressed
The source saysWhen aggravated or stressed, Japanese giant salamanders secrete a sticky, white mucus ... smells like Japanese peppersNote: tagline
The page saysoxygen-rich
The source sayscold, fast-flowing water where oxygen is in good supplyNote: habitat stat and body: 'the water carries plenty of oxygen'
The page saysFish, crayfish, insects, snails
The source sayseat a variety of animals, including fish, insects, crayfish, snails and small mammals
The page saysand small mammals
The source sayseat a variety of animals, including fish, insects, crayfish, snails and small mammalsNote: diet stat and body menu line
The page saysBreathes mainly through its wrinkled skin
The source says"breathe" primarily through their skin ... Flaps of skin, or wrinkles, increase the surface area for this respirationNote: superpower stat
The page sayshas sensory bumps around its head that work like a fish's lateral line
The source saysBumps on their skin, located mostly around the head, are actually external sensory organs that operate similarly to the lateral line system in fishNote: superpower stat
The page sayssecond-largest salamander species on Earth, after the Chinese giant salamanders
The source saysone of the largest salamander species in the world, second only to Chinese giant salamanders
The page saysIt can reach 1.5 meters (5 feet) long and weigh up to 23 kilograms (55 pounds)
The source saysreaching lengths of up to 5 feet (1.5 meters) and weighing up to 55 pounds (23 kilograms)
The page saysIts wrinkled skin is mottled black and brown
The source sayswrinkled skin mottled with varying patterns of black and shades of brown
The page sayswhere the water carries plenty of oxygen
The source sayslive in cold, fast-flowing water where oxygen is in good supply
The page saysIt can live for more than 70 years
The source saysThese salamanders can live for more than 70 years.
The page saysit breathes mainly through its skin
The source says"breathe" primarily through their skinNote: the Smithsonian's current 'primarily' replaces ADW's older all-skin, no-lung-breathing account
The page saysIts single lung is used mainly to control its buoyancy
The source sayssingle lung, but it is used primarily to control their buoyancy in the waterNote: 'how high or low it floats' defines buoyancy
The page saysIts eyesight is poor, so it hunts by smell and by sensing vibrations in the water
The source saysThey have poor eyesight, so they rely on smell and vibrations in the water when hunting.
The page saysBumps on its skin, mostly around the head, are sense organs that work like a fish's lateral line
The source saysBumps on their skin, located mostly around the head, are actually external sensory organs that operate similarly to the lateral line system in fishNote: the clause after it defines 'lateral line' for young readers
The page saysWhen aggravated or stressed, a Japanese giant salamander oozes a sticky white mucus that may be toxic to predators
The source saysWhen aggravated or stressed, Japanese giant salamanders secrete a sticky, white mucus that may be toxic to predators.
The page saysIt smells like Japanese pepper
The source saysThe sticky secretion has a pungent odor and smells like Japanese peppers.
The page sayswhich gave the species a Japanese name that translates to "big pepper fish"
The source saysThis has given them a common name in Japan that translates to "big pepper fish."Note: blockquote lead-in 'The Big Pepper Fish' is the same name
The page saysFrom August to October, the salamanders migrate upriver to spawn in dens: caverns, or burrows
The source saysThese salamanders spawn from August through October. During this season, they migrate upriver looking for "dens" — caverns or burrows
The page saysburrows 1 to 1.5 meters long in or near the riverbank
The source says100 to 150 centimeter) long burrows into or near the riverbank
The page saysThe largest, most dominant male on a stretch of river takes over a den
The source saysThe largest, most dominant male in a territory of river will occupy the den and defend it.
The page saysSeveral females may spawn in one den, each typically laying 400 to 600 eggs
The source saysmultiple females may enter the den and spawn with the male. Females typically lay a clutch of 400-600 eggs.Note: the Smithsonian's current 400-600 is used over ADW's 400-500
The page saysThe male, sometimes called the den master, fertilizes them, and once the females leave, protecting the eggs is his job
The source saysOnce the females have laid their eggs and the male has fertilized them, the females leave the den. It is now the male’s job to provide protection ... The male, sometimes referred to as the "den master,"
The page saysIncubation takes 40 to 60 days
The source saysThis incubation period ranges from 40-60 days.Note: the Smithsonian's current figure; ADW's older account gives 12 to 15 weeks
The page sayssecond-largest salamander species in the world, after the Chinese giant salamanders
The source saysone of the largest salamander species in the world, second only to Chinese giant salamandersNote: faq 1
The page saysIt can reach 1.5 meters (5 feet) long and weigh up to 23 kilograms (55 pounds), and it can live for more than 70 years
The source saysreaching lengths of up to 5 feet (1.5 meters) and weighing up to 55 pounds (23 kilograms) ... These salamanders can live for more than 70 years.Note: faq 1
The page saysWhen aggravated or stressed, it oozes a sticky white mucus that may be toxic to predators
The source saysWhen aggravated or stressed, Japanese giant salamanders secrete a sticky, white mucus that may be toxic to predators.Note: faq 2
The page saysThe secretion has a pungent smell like Japanese peppers, which gave the species a Japanese common name that translates to "big pepper fish."
The source saysThe sticky secretion has a pungent odor and smells like Japanese peppers. This has given them a common name in Japan that translates to "big pepper fish."Note: faq 2

Source
02

Animal Diversity Web, University of Michigan

Andrias japonicus. Animal Diversity Web, University of Michigan.

The page saysCold, fast-flowing, oxygen-rich mountain streams
The source sayscold, swift, mountain streamsNote: habitat stat; "fast-flowing" for "swift", which battleEngine.ts reads as a speed keyword
The page sayswestern Honshu and northern Kyushu, Japan
The source saysnative to the northern region of Kyushu Island and western Honshu island of JapanNote: habitat stat
The page saysworms
The source saysGiant Japanese salamanders also eat wormsNote: diet item ADW gives that the Smithsonian list doesn't
The page saysIts head is flat and wide
The source sayssit on the top of the wide, flat head
The page saysits eyes are small and lidless
The source saysSmall, lidless eyes sit on the top of the wide, flat head.
The page saysIt lives in cold, fast-flowing mountain streams
The source saysThese salamanders reside in and around the cold, swift, mountain streams of the Japanese islands.Note: "fast-flowing" for "swift", which battleEngine.ts reads as a speed keyword
The page saysin western Honshu and northern Kyushu, in Japan
The source saysnative to the northern region of Kyushu Island and western Honshu island of Japan
The page saysfrom 180 to 1,350 meters above sea level
The source saysfound at elevations between 180 and 1,350 meters
The page saysThis salamander has no gill openings
The source saysthese particular salamanders lack gill openings
The page saysWrinkles and folds add surface area for swapping oxygen and carbon dioxide with the water
The source saysThe wrinkles of the warty epidermis provide increased surface area, facilitating the exchange of carbon dioxide and oxygen with the water.
The page saystiny blood vessels called capillaries run close to the surface, so gases pass through easily
The source saysCapillaries run close to the surfaces of the skin, allowing for the easy diffusion of gases.
The page saysmales fiercely defend the same one for many years
The source saysMales ferociously defend and occupy a particular spawning pit for many years.
The page saysLarger males have killed and eaten smaller ones in the breeding season
The source saysSmaller males have been killed and eaten by larger males during the reproductive season.
The page saysstrung together like beads
The source saysheld together with a string-like substance and resemble threaded beads on a string

Source
03

Itami City, Cultural Promotion Division

オオサンショウウオを伊丹市内で見つけたら (If you find a Japanese giant salamander in Itami). Itami City, Cultural Promotion Division.

The page saysdangerLevel: Medium
The source saysオオサンショウウオは 目の前に動くものがあると反射的に噛みつきますNote: Itami City: it bites by reflex at anything moving in front of it, and a careless touch risks a bite. A bite to a person is 'can injure'; no source found states how serious bites are, and the page's 大変危険です ('very dangerous') is a warning against illegal capture, not an injury report, so it does not lift the tier to High
The page saysdangerLevel: Medium
The source says不用意に触ると噛みつかれる危険性もあり

Source
04

The IUCN Red List of Threatened Species 2022

Andrias japonicus. The IUCN Red List of Threatened Species 2022: e.T1273A177177761.

The page saysVulnerable
The source saysIUCN Red List category: Vulnerable (VU).

Source
05

Terry et al. 2018

Terry et al. (2018). Preoviposition paternal care in a fully aquatic giant salamander: nest cleaning by a den master. Journal of Zoology.

The page saysBefore spawning, one den master filmed at a zoo in Hiroshima paddled the nest floor with his front and hind legs every day
The source sayswe videotaped and examined a single den master's pre‐ and postoviposition behaviours at Asa Zoological Park in Hiroshima, Japan. The den master repeatedly exhibited vigorous movements of front and hind limbs in a paddling motion at the bottom of the nest every day
The page saysThat stirred up leaves and twigs buried in the sand, and the current carried them away
The source saysthe den master made the den filled with debris including leaves and twigs buried in the sand. The floating debris was subsequently removed by the water current flowing through the nest.
The page saysClearing that debris likely leaves less food for water mold, a major cause of death among the young
The source saysWater mould infection is a major cause of offspring mortality of aquatic amphibians including A. japonicus . By reducing the amount of organic matter that provides food sources for water mould, the nest cleaning likely reduces the risk

Source
06

Okada, Fukuda & Takahashi 2014

Okada, Fukuda & Takahashi (2014). Paternal care behaviors of Japanese giant salamander Andrias japonicus in natural populations. Journal of Ethology.

The page saysTwo den masters filmed with their eggs in natural streams
The source saysWe videotaped post-breeding behaviors of two den-masters that stayed with the eggs, one in a natural and the other in an artificial nest in natural streams.
The page saysfanned them with their tails to bring in oxygenated water
The source saysTail fanning provides oxygenated water for the eggs.
The page saysstirred them with their heads and bodies, which likely stops the yolk sticking
The source saysAgitating the eggs with its head and body likely prevents yolk adhesions.
The page saysThey also ate whiter eggs that looked dead or moldy, which likely keeps the mold from spreading to healthy eggs
The source saysThe den-masters selectively ate whiter eggs that appeared to be dead or infected with water mold. This behavior, which we termed hygienic filial cannibalism, likely prevents water mold from spreading over healthy eggs.
The page saysA den master is a large male that occupies a burrow along a stream bank for breeding and nesting
The source sayslarge males, called den-masters, occupy burrows along stream banks for breeding and nestingNote: faq 3
The page saysResearchers who filmed two den masters with their eggs in natural streams
The source saysWe videotaped post-breeding behaviors of two den-masters that stayed with the eggs, one in a natural and the other in an artificial nest in natural streams.Note: faq 3
The page saysfan the eggs with their tails to bring in oxygenated water
The source saysTail fanning provides oxygenated water for the eggs.Note: faq 3
The page saysstir them with their heads and bodies, which likely stops the yolk sticking
The source saysAgitating the eggs with its head and body likely prevents yolk adhesions.Note: faq 3
The page saysThey also ate whiter eggs that looked dead or infected with water mold, which likely stops the mold spreading to healthy eggs
The source saysThe den-masters selectively ate whiter eggs that appeared to be dead or infected with water mold. This behavior, which we termed hygienic filial cannibalism, likely prevents water mold from spreading over healthy eggs.Note: faq 3
The page saysThe researchers called this hygienic filial cannibalism
The source saysThis behavior, which we termed hygienic filial cannibalismNote: faq 3; the clause after it defines the term

Source
07

Takahashi, Okada & Fukuda 2016

Takahashi, Okada & Fukuda (2016). From embryos to larvae: seven‐month‐long paternal care by male Japanese giant salamander. Journal of Zoology.

The page saysone male stayed with his hatched larvae until they dispersed the following spring
The source saysWhile one male abandoned the nest, the other male remained in the nest and provided care until the larvae dispersed in the following spring.
The page saysseven months of care, from eggs to larvae
The source saysFrom embryos to larvae: seven‐month‐long paternal care by male Japanese giant salamanderNote: the figure is the reference's own title, which audit:sources matches against the DOI's Crossref record; the cached abstract does not repeat it

Source
08

Kawano et al. 2024

Kawano et al. (2024). Applying 3D Models of Giant Salamanders to Explore Form–Function Relationships in Early Digit-Bearing Tetrapods. Integrative And Comparative Biology.

The page saysweightKg: 7.8
The source says87 cm total length and 7.8 kg total weightNote: a measured large male ('Hiro'); settled in #533, which moved the value from ADW's 25 kg maximum

Source
09

Matsumoto, Fujiwara & Evans 2024

Matsumoto, Fujiwara & Evans (2024). The anatomy and feeding mechanism of the Japanese giant salamander (Andrias japonicus). Journal of Anatomy.

The page saysIt feeds by suction
The source saysTheir feeding behaviour is characterized by a form of suction feeding
The page saysThe side of its jaw closest to the prey drops open
The source saysasymmetric jaw movements are linked to the position of the prey in relation to the snout, with the jaw closest to the prey opening asymmetrically
The page saysthe salamander can hold its catch in one side of its mouth while pushing water out the other if its first suction attempt fails
The source saysallows the salamander to simultaneously grasp prey in one side of the mouth while ejecting water on the other side, if the first suction attempt fails
The page saysBy suction
The source saysTheir feeding behaviour is characterized by a form of suction feedingNote: faq 4
The page saysResearchers filming it feed found that the side of its jaw closest to the prey drops open
The source saysOur filming revealed that asymmetric jaw movements are linked to the position of the prey in relation to the snout, with the jaw closest to the prey opening asymmetrically.Note: faq 4
The page sayshold prey in one side of its mouth while pushing water out the other side if its first suction attempt fails
The source saysallows the salamander to simultaneously grasp prey in one side of the mouth while ejecting water on the other side, if the first suction attempt failsNote: faq 4

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.