Coastal Giant Salamander
Coastal Giant Salamander
Other names: Pacific Giant Salamander
The Coastal Giant Salamander is the only member of family Dicamptodontidae in Canada. They are the largest species of salamander in Canada, growing up to 30 cm in total length with broad heads and thick bodies. They have 12-13 indistinct , a laterally compressed tail, and dark, hardened toe tips specialized for digging and climbing. They are typically dark brown or black with a marbling pattern of tan or gold that tends to fade as they age and an off-white or light brown belly. individuals are not uncommon, and tend to grow slightly larger than terrestrial forms. Aquatic individuals are more often slate-gray to black and retain smaller gills compared to other neotenic salamander species, as they typically reside in more oxygen-rich environments that do not require as much gill surface area. Coastal Giant Salamander larvae have broad heads with feathery gills, front and back legs, and an obvious tail fin.
No other species of salamander in the range of the Coastal Giant grows quite as large and has a marbled brown or gold patterning. The Northwestern Salamander also grows quite large, but has , and is usually a uniform dark colour. The larval forms of other B.C. salamanders are not large enough to be confused with forms of the Coastal Giant Salamander.
Credit: Elke Wind
Coastal Giant Salamander
Credit: John Clare
Coastal Giant Salamanders have a very restricted range in British Columbia that is mainly within the Chilliwack River Valley and nearby tributaries of the Fraser River. They are most abundant in streams around Cultus and Chilliwack Lakes. In North America their range extends south of British Columbia into the western portions of Washington, Oregon, and northern California from sea level up to 1000 m. Some populations have been observed as high as 2200 m.
Coastal Giant Salamanders are associated with cool, flowing, mountain streams, usually in mature second growth, or old-growth coniferous forests with abundant litter, woody debris, or talus. They are often found in similar habitats to the Coastal Tailed Frog and have been known to prey on them. Larvae and neotenic individuals prefer small to medium-sized, cool, clear, and fast-flowing streams or creeks that have pools and available cover from boulders, logs, or cut-banks. Terrestrial adults spend the majority of their time in subterranean habitat and are difficult to observe. They are most active above ground during rainy evenings. Aquatic individuals and larvae may be easier to detect as they do not appear to disperse farther than 10-20 m from the section of stream they inhabit, and they may be found in high densities within suitable aquatic habitat.
The reproductive habits of the Coastal Giant Salamander are not well understood. They are thought to breed through the active season (between May and October), although females appear to only breed every other year. Males will deposit sperm packets (spermatophores) that are picked up by the female. Although few nests have ever been found, females appear to lay between 80-200 large eggs under rocks or logs within streams. Females are often found near nests, and it is assumed that they tend the nests until hatching occurs. Hatching usually occurs after about 6 months, although the newly hatched larvae do not leave the nest chamber for another 3-4 months. The larvae are fully aquatic and take 5-6 years to mature into adults.and terrestrial adults are common, although terrestrial forms are more common in smaller streams with limited aquatic habitat since these streams are more prone to drying up. The lifespan of Coastal Giant Salamanders is not known, although other large, aquatic salamanders may live up to 25 years.
Coastal Giant Salamanders are opportunistic carnivores with powerful jaws and a voracious appetite. Terrestrial adults will forage in upland forest habitats and eat a variety of invertebrate and vertebrate prey including insects, slugs, snails, worms, shrews, mice, and amphibians. Larval andindividuals eat aquatic invertebrates, amphibians and their larvae, and small fish.
The Coastal Giant Salamander is Red-Listed in B.C., and ‘Threatened’ in Canada, as nearly the entire range of the species in Canada is in the Chilliwack Valley. The primary threat to these large salamanders is logging and deforestation, as larva survival is heavily impacted by reduced forest cover and increased sedimentation in streams. Adult Coastal Giant Salamanders are very rarely found in unforested areas like clear-cuts. The protection of stream habitat and mature riparian forests will be critical in the conservation of Coastal Giant Salamanders.
Did You Know?
Coastal Giant Salamanders are one of the only salamander species that are capable of producing a vocalization! When they feel threatened, they will emit a low-pitched growling or barking sound.