Wildlife At Risk in British Columbia
A brochure series which will eventually include brochures on other Red 
and Blue listed species, including fish, invertebrates and plants, and on 
ecosystems. Produced by the Ministry of Environment, Lands and Parks, 
Wildlife Branch, 780 Blanshard St. Victoria, BC V8V 1X4. For copies of this 
brochure, write to the Wildlife Branch. Funded by Corporate Resource 
Inventory Initiative and Ministry of Environment, Lands and Parks.
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British Columbia’s largest salamander is probably declining due to 
expanding towns, intensive agriculture, and the effects of logging.


Why are Pacific Giant Salamanders at risk?
Although the Pacific Giant Salamander is found along the west coast of 
North America from northern California to southern British Columbia, it 
has an extremely limited range in this province. Its range extends into 
British Columbia only in the Chilliwack River watershed and immediately 
adjacent areas, about 100 kilometres east of Vancouver. Its total range in 
British Columbia is about 250 square kilometres, a meagre 0.03 percent of 
the area of the province. The species has been observed at only a few 
dozen locations within that range over the past 65 years and does not 
occur elsewhere in Canada.

The distribution range of Pacific Giant Salamanders in British Columbia is 
limited by barriers that include the Fraser River and adjacent farmlands to 
the north and west, and by the colder and drier inland climate to the east. 
Their upper elevational limit, about 1050 metres, is probably also set by 
winter climate. Within their general range in the Chilliwack watershed 
and vicinity, their distribution and abundance is limited by the availability 
of suitable stream habitats. Experts feel that the species is probably 
declining in abundance due to the effects of development and industry on 
streams and on riparian (streamside) habitats, which are critical for its 
survival. However, the actual population size is not known, and would be 
very difficult to determine.

Human activities, such as the drainage of Sumas Lake and land 
development for farming and settlement along Vedder Mountain and in 
the Cultus Lake area, may have reduced the British Columbia distribution 
range of the Pacific Giant Salamander. Other activities, such as logging, 
have probably had detrimental effects in some areas, particularly where 
all streamside forest has been removed and small creeks are choked with 
debris. Poor logging practices can result in more variable streamflows, 
erosion and siltation of stream habitats, removal of streamside cover, and 
increased water temperature. These effects are all detrimental for 
salamanders and for many of the species they depend on for food.

A major cause of mortality of Pacific Giant Salamanders is probably 
predation. Reported predators in the United States include garter snakes, 
River Otters, weasels and Water Shrews, species that also occur here. 
Other likely predators include Mink, trout, and Dolly Varden Char. The 
natural reproductive rate is normally high enough to overcome such 
losses. In good habitat, enough salamanders survive to breeding age to 
maintain the population, despite some losses caused by predation.

Extreme climate events, such as summer drought and resulting 
desiccation, severe winters, or debris torrents down streams during record 
rainfall, can adversely affect salamander habitat. However, to persist in 
this area, the salamanders have obviously been able to recover from these 
periodic natural events. 

What is their status?
Like most other wildlife in the province, the Pacific Giant Salamander is 
protected from killing or collecting under the Wildlife Act. Using criteria 
such as the limited extent of its distribution, its low reproductive rate, and 
the rate of habitat loss, it has been classified by BC Environment as a 
“species at risk” and placed on the Red List - the category of greatest 
concern. Red-listed species are those being considered for legal 
designation as “Threatened” or “Endangered.” It is designated by the 
Committee on the Status of Endangered Wildlife in Canada (COSEWIC) 
as “Vulnerable.”

The Pacific Giant Salamander has the most restricted distribution range of 
any of the 18 species of amphibians that are native to British Columbia. It 
is a good example of a “peripheral” species – one that is relatively 
widespread outside of this province but only barely extends into it. For 
genetic reasons, peripheral species are considered by BC Environment to 
be of provincial management concern, and conservation efforts for them 
emphasize habitat preservation.

In British Columbia, this unique large amphibian has been recorded along 
streams of the Chilliwack River drainage from Vedder Crossing to the 
United States border and in nearby areas such as Bridal Veil Creek, and 
small streams along the west side of Vedder Mountain. All British 
Columbia records are from below 1050 m elevation. Searches have so far 
failed to find the species in adjacent areas south of the Fraser River, such 
as the Silverhope and Skagit valleys or Sumas Mountain. The Fraser River 
is a major barrier to northward dispersal.

This salamander is more widely distributed in Washington, Oregon, and 
northern California, occurring in suitable habitats from the coast inland to 
the crest of the Cascade Range. Closely related species, which were until 
recently considered to be varieties of the Pacific Giant Salamander, occur 
along the central coast of California, on the Olympic Peninsula, and in 
Idaho.

What do they look like?
Like most salamanders, the Pacific Giant Salamander (Dicamptodon 
tenebrosus) has gill-breathing larvae that live entirely in water, and 
terrestrial (land-dwelling) adults. In British Columbia, transformation 
from larva to adult occurs at about five to six years of age, when the larvae 
have reached a size of 15-20 centimetres. However, some larvae continue 
to grow to adult size and become sexually mature without losing their 
gills. This process is called neoteny, and these individuals are referred to 
as neotenes. Neoteny is common in this species in British Columbia.

As its name implies, this is a large salamander; in fact, it is the largest 
salamander in British Columbia. Adults and neotenes are stout-bodied 
and may reach 30 cm or more in total length. Like all salamanders, this 
one has four toes on the front feet, five toes on the hind feet, and a tail. The 
tail, about 40 percent of the total length, is laterally compressed (from side 
to side, like an eel) as an aid for swimming.

Although secretive and seldom seen, adults are readily identified by their 
colouring. The head, back, and sides have a distinctive marbled or 
reticulate pattern of dark blotches on a light brown or brassy-coloured 
background. The belly is a uniform slate or tan colour. The broad head has 
a shovel-like snout, and a fold of skin (the gular fold) across the throat. 
The eyes are medium-sized and have a brass-flecked iris and large black 
pupil. Adult-sized neotenes have a uniform brown colouring on their 
heads, backs and sides in contrast to the marbled pattern of transformed 
adults, and they retain their external gills. Colour varies considerably 
throughout the range of this salamander.

Larvae of the Pacific Giant Salamander are streamlined and adapted for 
life in flowing water. They have small, fuzzy gills behind their heads and a 
fin around the top and bottom of their tails. Young larvae have tiny, 
scattered dark brown or black patches on their backs, sides and upper 
surface of their tails. 

The Pacific Giant Salamander is the only salamander in British Columbia 
that normally occurs in fast-flowing mountain streams. Salamander 
larvae, adults, or neotenes observed in clear mountain streams in the 
Chilliwack River area are almost certain to be of this species.

What makes them unique?
The Pacific Giant Salamander is particularly elusive, moving about and 
feeding mostly at night, and hiding by day. It tends to be least active and 
most hidden in winter, a response to cold weather. Consequently, little is 
known about the behaviour of this salamander in the wild, particularly in 
British Columbia. Almost all research on the Pacific Giant Salamander has 
been carried out in the United States.

Larvae and neotenes live entirely in the water. Transformed adults visit 
streams to breed but, because they have lungs, can live out of the water 
and hence are called “terrestrial.” During the day, adults are usually 
hidden in crevices along streams, or under rotten logs, rocks, or other 
cover in adjacent forests. Adults are capable diggers and climbers, and 
have cornified (hardened) toes for this purpose. They frequently dig into 
surface material to find food or protective cover. They avoid brightly lit 
areas and direct sunlight, and prefer damp surroundings where their skin 
will not dry out.

Adults often display aggressive behaviour toward others of their kind or 
potential predators. They will defend small caverns against subordinate 
individuals, an indication of territoriality. If threatened or attacked, adults 
engage in biting and tail- thrashing, and generally try to look as 
formidable as possible. Foul-tasting secretions from glands on the top of 
the tail also aid in defence. This species is said to produce sounds 
described as “rattles,” “barks,” or “growls,” but researchers in British 
Columbia have not observed this here. The tendency to vocalize and to 
use defensive postures varies from place to place, and little study has been 
done in British Columbia.

How do they reproduce?
Sexually mature individuals of the Pacific Giant Salamander migrate to 
suitable streams or springs for breeding, which is believed to occur from 
spring to autumn. The female deposits from 85 to 200 eggs, singly or in 
clumps, in a hidden subterranean or underwater nestsite. The eggs are 
white, 15 to 20 millimetres in diameter, and each is attached to the roof of 
the underwater nest cavern by a short stalk. The female broods and 
protects these eggs for up to seven months. During this period she 
aggressively protects them from being cannibalized by males or eaten by 
other predators, and eats little or nothing herself. At hatching, the larvae 
are about 3 cm long, including the tail, and have a large yolk sac. The 
larvae stay in the nest area and live off their yolk for a further two to four 
months, finally beginning to hunt for small prey when about 4 cm in 
length. Growth is slow in the cold mountain streams preferred by this 
salamander, particularly in British Columbia where larvae may not be 
sexually mature for five or six years.

Several characteristics of the Pacific Giant Salamander result in a low 
reproductive rate compared to many other amphibians. These 
characteristics include the relatively small number of eggs produced, a 
long egg-brooding period that allows females to breed only about every 
second year, and a period of several years required to reach sexual 
maturity.

What do they eat?
Foods of the Pacific Giant Salamander have not been determined in British 
Columbia, but are likely to be similar to those eaten by this species in the 
United States. Larvae and adults are all predatory, and may even be 
cannibalistic. Larvae of aquatic insects are important prey, including 
mayflies, stoneflies, caddisflies, and true flies such as mosquitoes and 
blackflies. Other aquatic food items include worms, snails, small fish, and 
tadpoles of the Tailed Frog, which also occur in mountain streams. Adult 
salamanders occasionally eat land insects, such as beetles, aphids, ants, 
and grasshoppers, as well as spiders and slugs. Large individuals can 
capture sizeable prey, including shrews, mice, Northwestern Salamanders, 
and even small garter snakes.

Where do they live?
Throughout its North American range, the Pacific Giant Salamander is 
found in a variety of aquatic habitats, including lakes, ponds, rivers, and 
streams. In British Columbia, most records are from relatively small 
streams between 100 and 1050 m elevation in coastal coniferous forests. 
There are a few records from Cultus and Chilliwack Lakes and the 
Chilliwack River. Transformed adults also live in moist uplands beside 
streams or lakes.

In British Columbia, streams where this salamander breeds and rears 
larvae are generally small, permanent ones with moderate to fast flows, 
and water that is clear, cool, and well oxygenated. Some of these may 
almost dry up in summer, consisting then of a series of pools connected by 
underground flow. Most have tall streamside vegetation that provides 
shade and prevents over-heating in summer. Warm, murky lowland 
streams, swamps, or ditches, so attractive to many kinds of amphibians, 
are not suitable for the Pacific Giant Salamander.

Cover is very important for this species for hiding from predators, 
protection from the sun, brooding eggs and resting. Small larvae burrow 
into gravelly streambottoms to hide. Larger larvae and adults in streams 
find protection under overhanging banks, in crevices in the bedrock, or 
under submerged logs or large boulders and rubble. The best streams 
have numerous pools with complex bottoms composed of a mixture of 
boulders and sand. Terrestrial adult salamanders also need cover when 
away from streams. Mature and old-growth forests with plenty of shade 
and with considerable litter and debris, such as rotting logs on the forest 
floor, are preferred habitats. These provide protection from the elements, 
many moist dark hiding places for the salamanders, and a variety of 
habitats for insects and other prey. 

What can we do?
Assignment of this uncommon salamander to the provincial Red List 
(candidates for Threatened or Endangered status) ensures that the species 
will receive priority attention in government conservation programs. The 
Conservation Data Centre maintains a database of information on rare 
species in British Columbia, including this salamander.

Although the Pacific Giant Salamander is protected under the provincial 
Wildlife Act, only a few small areas of potential habitat are protected in 
parks. Most of its habitat is on Crown land managed for forestry, and the 
impact of logging is a serious concern. Management of this elusive 
amphibian is largely a matter of protecting its remaining habitat.

Pacific Giant Salamanders presently occur in streams through second-
growth forests that were logged in past decades, indicating that they can 
persist or reestablish in logged areas. Nevertheless, streams occupied by 
this vulnerable species should receive protection from adverse effects of 
logging practices.

Routine referral of logging plans and other significant development 
proposals to BC Environment Habitat Protection staff allows potential 
impacts on salamander habitat to be identified. In such cases, 
recommendations are made concerning retention of streamside 
vegetation, road location, culvert design or other pertinent measures, to 
avoid siltation into streams or blockage of salamander movement along 
them. Regional staff are preparing guidelines for culvert design and 
installation in streams supporting Pacific Giant Salamanders. Laws and 
guidelines for protection of fish- bearing streams afford only limited 
protection for this species because the salamanders often inhabit minor 
streams and headwaters that do not support salmonids.

Recent government-sponsored research has improved our knowledge of 
the local distribution and ecology of this unique amphibian, but much 
remains to be done. Thorough searches of many small streams are still 
needed. More information on habitat preferences and on impacts of 
logging and silvicultural practices would aid in protection and 
management.

The public is urged to become more familiar with this little-known 
member of our fauna. Any sightings of it, or observations of activities that 
threaten its habitat, should be reported to the nearest BC Environment 
office. With your support, the Pacific Giant Salamander and other rare 
species will continue to enrich this diverse province.