---
title: "What the sources say about the Pacific Giant Salamander | AnimalTracks.wiki"
description: "50 claims from the Pacific Giant Salamander profile, each beside the words of the source that backs it."
image: "https://animaltracks.wiki/images/animals/pacific-giant-salamander-1.webp"
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---

# What the sources say about the Pacific Giant Salamander (*Dicamptodon tenebrosus*)

> 50 claims from the Pacific Giant Salamander profile, each beside the words of the source that backs it. A "..." marks a cut in a quote and [brackets] an insertion.

Profile: [Pacific Giant Salamander](https://animaltracks.wiki/animals/pacific-giant-salamander/)

## Dicamptodon tenebrosus (Coastal Giant Salamander). Animal Diversity Web, University of Michigan.

https://animaldiversity.org/accounts/Dicamptodon_tenebrosus/

| The page says | The source says |
| :--- | :--- |
| 17 cm | Adults measure 6.25 to 17 cm snout-vent length (SVL) (note: ADW's upper SVL bound, matching WDFW's 6.7 inches; the body says 'up to'.) |
| adults weigh between 22 and 114 grams | Adult mass ranges from 22 to 114 g. |
| Along the coast from northern California through Oregon and Washington into southwestern British Columbia | Pacific giant salamanders occupy the coastal areas of British Colombia, Oregon, Washington, and northern California. In British Colombia, these salamanders are only found in the extreme southwest region, south of the Fraser valley and in the Chilliwack district. |
| from sea level up to about 1,830 meters | This species can be found at elevations from sea level to 1830 m. |
| is mostly active at night | Pacific giant salamanders are mostly nocturnal, though may be active during the early morning hours as well. |
| Disturbed salamanders arch their backs, sometimes thrash their tails, and let out an audible growl or bark | When disturbed by predators Pacific giant salamanders will emit a "bark". When approached by a predator, individuals strongly arch their bodies and may thrash their tails to threaten the predator. |
| adults will also head-butt and bite viciously | The adults of this species will also head butt and bite viciously. |
| Weasels, river otters, water shrews and garter snakes are among its documented predators | Natural predators of Pacific giant salamanders are weasels, river otters, water shrews, garter snakes (Thamnophis genus), salmonids and conspecifics. |
| Eggs take up to seven months to hatch into larvae about 3 centimeters long | After they are laid, the eggs may take up to 7 months to hatch. Larvae are 3 cm long upon hatching |
| which live off a large yolk sac for two to four months, then start hunting for themselves | and feature large yolk sacs that will sustain them for 2 to 4 months. At this point, the young are about 40 cm in length, and can begin to hunt their own prey. (note: Body drops ADW's '40 cm' figure for the young at this stage: it exceeds the species' own adult maximum (34 cm total length) and reads as a data error on ADW's dated page, so it is not repeated.) |
| Cannibalism among coastal giant salamanders is well documented in males | Cannibalism is well documented among the males of the species |
| it may be why a female stands guard over her eggs | which may explain why the female is in attendance. |
| for six or seven months | Range time to hatching 6 to 7 months. |
| cold | environmental conditions (such as the cold temperature of preferred streams) affect the growth and survival of the larvae |
| low-silt | with very little silt on the bottom of the stream |
| in rainy spells it can turn up beneath leaf litter in the moist conifer forest nearby | During rainy periods this species may also be found under forest litter such as leaves and small branches. |
| They can also secrete a noxious substance from the tail to ward off predators | They can also secrete a noxious substance from their tails to ward off predators. |
| working through insects, amphipods, mollusks and crayfish | They will consume insect larvae and adults, amphipods, ostracods, termatoes, mollusks, and crayfish. (note: 'termatoes' as printed on the ADW page is left out; it reads as a typo.) |
| with larger larvae sometimes adding fish and other salamanders to the menu | Larger larvae will prey on some salmonids, sculpins, and salamanders. |
| The species hunts by sitting and waiting, then lunging a short distance | Pacific giant salamanders are sit and wait predators who quickly lunge short distances in order to obtain prey. |
| large adults on land can take mice, shrews and even snakes | Large terrestrial members of the species can handle eating small mammals such as mice and shrews or even snakes. |
| In British Columbia, nearly all of them keep their external gills for life instead of completing metamorphosis | the aquatic being neotenes which retain many larval characteristics like external gills. Neoteny seems to be more prevalent in certain, more coastal populations, specifically, British Colombia salamanders are nearly all neotenes. |
| Even these gilled adults sometimes move out of the stream in rainy, wet weather | The newly metamorphosed and sometimes paedomorphic individuals move out of streams during rainy, wet periods. |
| takes five or six years | Pacific giant salamanders exhibit slow growth rates and do not reach sexual maturity until 5 or 6 years of age. |
| The species is one of its own predators | Natural predators of Pacific giant salamanders are weasels, river otters, water shrews, garter snakes (Thamnophis genus), salmonids and conspecifics. |
| Gravel-and-boulder mountain streams and moist conifer forest from northern California to southwestern British Columbia | Pacific giant salamanders occupy the coastal areas of British Colombia, Oregon, Washington, and northern California. ... The type of stream bed they prefer is composed of large gravel to small boulders |
| Insects, amphipods, mollusks and crayfish as larvae; mice, shrews and even snakes as large adults on land | They will consume insect larvae and adults, amphipods, ostracods, termatoes, mollusks, and crayfish. ... Large terrestrial members of the species can handle eating small mammals such as mice and shrews or even snakes. |
| An audible warning bark and a noxious tail secretion, backed up by a head-butt and a vicious bite. | When disturbed by predators Pacific giant salamanders will emit a "bark". ... They can also secrete a noxious substance from their tails to ward off predators. The adults of this species will also head butt and bite viciously. |
| Yes. A disturbed one gives a bark, and it can also make a rattling or growling noise while it snaps its jaws and lashes its tail. | When disturbed by predators Pacific giant salamanders will emit a "bark". ... They often produce a rattling or growling sound while snapping their jaws and lashing their tail. |
| No harmful effects on people are known. | There are no known adverse effects of dicamptodon tenebrosus on humans. |
| A salamander facing a predator still has a full kit of defenses, from tail lashing and biting to skin secretions, plus a warning bark. | When approached by predators salamanders employ a variety of anti-predator adaptations. These include tail lashing, biting, arching of the back, and skin secretions. They are also known to emit a warning bark. (note: 'known to emit a warning bark' is ADW's standing statement of the behaviour, not a hedge on whether it happens; the body's bark claim quotes ADW's flat 'will emit a "bark"'.) |
| Counted one by one, most of an adult's prey comes from the water, but by volume it eats more land animals. | Adult diets are dominated numerically by aquatic organisms but they consume a higher volume of terrestrial prey. (note: 'most ... by count' paraphrases 'dominated numerically'; 'more ... by volume' is 'a higher volume of terrestrial prey'.) |
| Big adults foraging the forest floor on rainy nights can take mice, shrews and even snakes. | Terrestrial adults emerge from logs and other surface cover on rainy nights and forage the forest floor. ... Large terrestrial members of the species can handle eating small mammals such as mice and shrews or even snakes. |
| No. Gilled adults are common in coastal populations, and in British Columbia almost every one skips metamorphosis for good. | Gilled, aquatic adults are common in more coastal populations and in those of British Columbia. ... British Colombia salamanders are nearly all neotenes. |
| dangerLevel: Low | There are no known adverse effects of dicamptodon tenebrosus on humans. |
| tags: forest | During rainy periods this species may also be found under forest litter such as leaves and small branches. |
| A disturbed coastal giant salamander does the same, arching its body, sometimes thrashing its tail, and emitting a bark. | When disturbed by predators Pacific giant salamanders will emit a "bark". When approached by a predator, individuals strongly arch their bodies and may thrash their tails to threaten the predator. |

## Pacific giant salamander (Dicamptodon tenebrosus). Washington Department of Fish and Wildlife.

https://wdfw.wa.gov/species-habitats/species/dicamptodon-tenebrosus

| The page says | The source says |
| :--- | :--- |
| North America's largest terrestrial salamander | The largest terrestrial salamander in North America; adults reach lengths of 6.7 inches snout-vent length and 13.4 inches total length. |
| the biggest land salamander in North America | The largest terrestrial salamander in North America |
| 6.7 inches | adults reach lengths of 6.7 inches snout-vent length |
| 13.4 inches | 13.4 inches total length |
| 34 cm | adults reach lengths of 6.7 inches snout-vent length and 13.4 inches total length (note: 34 cm is the conversion of WDFW's flat 13.4 inches (current state agency page); ADW gives the same figure as 'may reach 34 cm'. The body says 'up to', which carries ADW's hedge as a maximum.) |
| By day its stream forms usually hide under rocks and woody debris | Larvae and gilled adults can be observed day or night in streams. During the day, they are typically concealed under rocks or woody debris |
| mountain streams | Pacific giant salamanders are primarily associated with small to medium-sized mountain streams in moist coniferous forests. |
| moist conifer forest | small to medium-sized mountain streams in moist coniferous forests |
| Larvae spend 18 months to two years in the stream | The larval period is 18 to 24 months or may be permanent (gilled adults) depending on local conditions. (note: WDFW's 'may' governs only the permanent (gilled adult) alternative, which the body covers separately; ADW: 'Metamorphosis begins 18 to 24 months after hatching'.) |
| yet they still become sexually mature | Sexual maturity takes place in all forms that are around 4.5 inches snout-vent length. |
| maturity comes at around 4.5 inches (11 cm) from snout to vent | Sexual maturity takes place in all forms that are around 4.5 inches snout-vent length. (note: 11 cm is the conversion of WDFW's 4.5 inches (11.4 cm).) |
| Washington's wildlife agency notes that the larval stage can be permanent, depending on local conditions. | The larval period is 18 to 24 months or may be permanent (gilled adults) depending on local conditions. |

## Dicamptodon tenebrosus. The IUCN Red List of Threatened Species 2022: e.T59081A196338656.

https://doi.org/10.2305/iucn.uk.2022-1.rlts.t59081a196338656.en

| The page says | The source says |
| :--- | :--- |
| Least Concern | IUCN Red List category: Least Concern (LC). (note: Category read through GBIF's copy of the Red List (iucnredlist.org refuses scripts); binomial and taxon id (59081) checked against the assessment DOI, per verify:quotes.) |