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BC Conservation Data Centre: Species Summary


Plethodon idahoensis
Coeur d'Alene Salamander

 
Scientific Name: Plethodon idahoensis Slater and Slipp, 1940
English Name: Coeur d'Alene Salamander
 
Classification / Taxonomy
Scientific Name - Concept Reference: Frost, D. R. 1985. Amphibian species of the world. A taxonomic and geographical reference. Allen Press, Inc., and The Association of Systematics Collections, Lawrence, Kansas. v + 732 pp.
Classification Level: Species
Species Group: Vertebrate Animal
Species Code: A-PLID
Kingdom Phylum Class Order Family
Animalia Craniata Amphibia Caudata Plethodontidae
   
Conservation Status / Legal Designation
Global Status: G4 (May 2016)
Provincial Status: S3? (Jan 2022)
BC List: Blue
Provincial FRPA list: Y (May 2004)  
Provincial Wildlife Act:
COSEWIC Status: Special Concern (May 2021)
SARA Schedule: 1  -  Special Concern (Jun 2003)
General Status Canada: 3 - Sensitive (2005)
   
Ecology & Life History
General Description: A small, black lungless salamander with a yellowish throat patch, and a yellow, orange, green, or red dorsal stripe. The stripe usually has scalloped edges. Legs are relatively long with short, slightly webbed toes.
Subspecies Comments: No subspecies known
Identification Comments: Black or dark brown body colour with uneven dorsal stripe and pale yellow gular patch. Numbers and sizes of irregular lateral projections and blotches along the stripe are variable from individual to individual. All seen in BC have yellow-orange stripe, except two individuals with brick-red stripe. Parotoid glands present and short toes slightly webbed. Maximum size encountered in BC was 65 mm snout-vent length (to anterior of vent). Minimum size was 18 mm (neonate). Adult males with mental gland, vent lobes and nasolabial cirri.
Global Reproduction Comments: Coeur d'Alene salamanders mate above ground in late summer and fall (August-October) and, to a lesser extent, in spring (April and May) (Lynch 1984). After a courtship ritual of an hour or more, the male deposits a spermatophore. The sperm cap is picked up by the female with the cloaca (Lynch and Wallace 1987). Females store sperm up to nine months before fertilizing eggs. An average of six eggs is deposited in April or May. The young emerge in mid-September (Lynch 1984).

Neonates apparently grow more slowly than other PLETHODON. Growth probably occurs in spurts associated with wet weather in the spring and fall. Male Coeur d'Alene salamanders reach sexual maturity at 3.5 years of age and females at 4.5 years, but some individuals may delay breeding. Males mate every year, whereas females mate in alternate years (Lynch 1984).
Provincial Reproduction Comments: In Canada, neonates have been found in late spring. Preliminary information on growth rates indicated a mean growth rate (from 28 May to 16 Oct 2000) of .05 mm (n = 11, SD = .01, range .03 -.07 )(SVL) per day (Ohanjanian 2001b) . Courtship has been observed in September in Canada (Ohanjanian and Teske 1996).
Provincial Ecology Comments: Individuals appear to spend a high percentage of their time underground. Preliminary mark-recapture studies in southeastern BC indicated that the surfacing rate may be quite infrequent, and conclusive information about population trends has not been gathered. Juveniles (indicating that reproduction was taking place) were observed in four of five years at a monitoring site (visited in 1995 (no juvs), 1996, 2001, 2002 and 2003.) Juveniles observed in May/June at another site were small and included neo-nates (18 mm SVL). Not only were they smaller than juveniles seen in the fall, but there was a higher proportion of juveniles to adults detected in spring/summer survey period. This suggests that hatching occurs in the spring, and that mortality of the smallest and most vulnerale size classes occurred during the summer/early fall (Ohanjanian 2001).
Migration Characteristics:
(Global / Provincial)		 
    Nonmigrant:
    Local Migrant:
    Distant Migrant:
    Within Borders Migrant: 		Y / Y
N / N
N / N
na / N
Provincial Mobility & Migration Comments: The longest distance moved by a salamander recorded in one fall season (2000) was 52.8 m laterally away from a waterfall. Same animal re-located back at waterfall in 2002 for a total minimum travel distance of at least 103.6 m. In 2003, an individual was detected at a normally dry, rocky outcrop during the rain, 50 m away from a known occurrence site (a steep stream).
Habitats:
(Type / Subtype / Dependence) 		Forest / Conifer Forest - Moist/wet / Unknown
Other Unique Habitats / Splash Zone / Unknown
Riparian / Riparian Forest / Unknown
Rock/Sparsely Vegetated Rock / Cliff / Unknown
Rock/Sparsely Vegetated Rock / Rock/Sparsely Vegetated Rock / Unknown
Rock/Sparsely Vegetated Rock / Talus / Unknown
Stream/River / Stream/River / Unknown
Subterranean / Caves / Unknown
Subterranean / Sub-soil / Unknown
Global Habitat Comments: Primary habitats are seepages and streamside talus; also inhabits talus far from free water (deep talus mixed with moist soil on well-shaded north-facing slopes); in wet weather, occurs also in leaf litter and under bark and logs in coniferous forest. Terrestrial breeder; eggs presumably are laid in underground rock crevices, although no nest sites have been found in the wild.

All plethodontid salamanders respire through their skin; terrestrial species lose water to the environment through evaporation and are therefore restricted to cool, damp environments. Because Coeur d'Alene salamanders may live in the harshest climate of any northwestern PLETHODON (Nussbaum et al. 1983), they are highly dependent on the thermal and hydric stability provided by wet habitats in otherwise inhospitable surroundings. For this reason, Coeur d'Alene and the closely related Van Dyke's salamanders are closely tied to water and are considered among the most aquatic PLETHODON (Brodie and Storm 1971).

Coeur d'Alene salamanders have been found in three major types of habitat: springs or seeps, waterfall spray zones and edges of streams. Seventy-six percent of known locations are classified as seeps, 6% as waterfalls, and 17% as streams. One percent (two sites) are in abandoned mine shafts. However, the relative number of locations in each type is biased by differences in survey efficiency and probably does not reflect the importance of the different habitats. The abundance of seep locations is at least partly due to the relative ease of surveying roadside seeps. Streams and waterfalls are often less accessible, particularly at night. Salamanders are most difficult to find in streamside habitat, where they are usually observed underneath moist rocks on the banks adjacent to the water. Searches of 30 minutes to find a salamander at a stream site during daylight are not uncommon (Groves 1988).

Coeur d'Alene salamander occurrences are generally located in coniferous forest, but are not restricted to a particular overstory species or aspect. Populations have been found in areas with ponderosa pine (PINUS PONDEROSA), Douglas-fir (PSEUDOTSUGA MENZIEZII), western larch (LARIX OCCIDENTALIS), western red cedar (THUJA PLICATA) and western hemlock (TSUGA HETEROPHYLLA) overstories (Groves 1988) at all aspects.

Ninety percent of 99 Idaho occurrences where habitat data have been collected were in areas of greater than 25% canopy cover and only two (both seeps) were in an area with 10% cover or less. Forest cover may be more important near stream sites than seep sites. Average cover at streamside sites (83% + or - 15%) was significantly greater (Mann-Whitney U, P = 0.005) than at seep locations (57% + or - 5%), although only seven stream sites were measured (Cassirer et al. 1994). Minimum canopy cover measured at stream sites was 42%. Terrain at sites was typically steep, with average slopes of 62% (range 10-90%) (Groves 1988, Wilson 1991).

Known populations occur in association with sharply fractured rock formations (used for underground refugia) from 488 m to 1,524 m in elevation. This fractured rock is often found in the Belt Rock formation but can also occur in talus and in other geologic types (Wilson and Simon 1987, Groves and Cassirer 1989). The species is found in conjunction with both persistent and intermittent surface water. Thus, it is possible to locate salamanders at a wet site in the spring, yet be unable to find any animals at the same site later in the summer when the site is dry on the surface.
Provincial Habitat Comments: Occupies steep gradient creeks, waterfall splash zones, rock walls or caves with seepages, deep, wet talus, and avalanche paths where there is fissured bedrock associated with moisture. They retreat underground to interstitial spaces in winter (to escape cold) and summer (if excessively hot and dry). Species is nocturnal, so during the day they may also be in subterranean habitat or on the surface under moist cover objects.
Food Habits: Invertivore: Adult, Immature
Global Food Habits Comments: When above ground, Coeur d'Alene salamanders feed primarily on insects and other invertebrates (Wilson and Larsen 1988). They appear to be opportunistic feeders and generally restrict foraging activities to moist spray zones, seeps, or streamside rocks and vegetation although they may venture beyond these areas during rainy periods.
Provincial Food Habits Comments: No studies on food habits in B.C. Montana work showed prey to be primarily insects, including aquatic larval forms of Hemiptera, Plecoptera, Ephemeroptera, as well as Diptera adults and larvae, Homoptera at various developmental stages and adult Coleoptera. Other non-insect invertebrates, including spiders, oligochaetes and gastropods were ingested as well. Foraging has been observed at the edges of pools that collect at the base of seepages. It is likely that, as opportunistic feeders, they will attack prey wherever they are encountered. The relative amounts of foraging that take place on the surface vs sub-surface is not known. Because individuals are underground for such extended periods of time, it is probable that an invertebrate food source is available in subterranean retreats.
Global Phenology: Hibernates/aestivates: Adult, Immature
Global Phenology Comments: Coeur d'Alene salamanders are adapted to a severe environment. The salamanders are usually above ground only at night during moist weather in the spring and fall (Nussbaum et al. 1983), although at some sites salamanders exhibit nocturnal surface activity throughout the summer. Summer surface activity in seeps is negatively correlated with high daytime temperatures and days since last rain (Wilson and Larsen 1988).

Overall, the salamanders may spend up to seven months of the year underground in cool, moist interstitial spaces between rocks to avoid desiccation in summer and freezing in winter. This extensive underground activity presents a major challenge to research and monitoring.

In northern Idaho, emergence from winter hibernation occurs in late March, surface activity occurs in April-May; retreats underground (except near seepages and waterfalls) from June to mid-September, active again with September-early November rains, then hibernates until March.
Provincial Phenology:
(1st half of month/
2nd half of month)		 Jan: Present / Present
Feb: Present / Present
Mar: Reproducing / Reproducing
Apr: Reproducing / Reproducing
May: Active / Active
June: Active / Active
July: Active / Active
Aug: Active / Active
Sept: Reproducing / Reproducing
Oct: Active / Active
Nov: Active / Present
Dec: Present / Present
Provincial Phenology Comments: Most active on surface in spring and fall, but may also be active in summer at waterfall sites or if conditions at seepages are moist.
Colonial Breeder: N
Length(cm)/width(cm)/Weight(g): 12/ /
Elevation (m) (min / max): Global: 
Provincial:  570 / 1365
   
 
Distribution
Endemic: N
Global Range Comment: The Coeur d'Alene Salamander is a remnant of a once diverse plethodontid salamander fauna in the central Rocky Mountains that was likely reduced by climatic changes over the last 10-14 million years (Nussbaum et al. 1983, Tihen and Wake 1981). The species maintains a disjunct distribution at elevations up to 1,524 m (5,000 ft) in northern Idaho, western Montana, and southeastern British Columbia (Wilson et al. 1997; Wilson and Ohanjanian 2002). The North Fork of the Clearwater and the St. Joe drainages in Idaho, and the lower Clark Fork and Kootenai Rivers in Montana, comprise the core of the species distribution (Wilson and Simon 1987, Genter et al. 1988, Groves 1988). The Selway River drainage comprises the southern limit of the known range in Idaho (Wilson 1990) and Copper Creek and the Moyie River drainage the northern limit (Wilson et al. 1989). In Montana, the southern limit of known distribution is Lake Como Falls in the Bitterroot River drainage (Maxell 2002) and the northernmost population is along the South Fork of the Yaak River (Wilson and Simon 1987; Maxell et al. 2003). Coeur d'Alene Salamanders are currently known from about 15 locations in British Columbia, from 95 km north of Revelstoke to a cluster of locations mostly along the southeast corner of Kootenay Lake (Holmberg et al. 1984; Orchard 1990; Charland 1992; Wilson and Ohanjanian 2002).

Although not all localities of occurrence have been identified, the southern, eastern and western edges of the distribution are likely limited by lack of moisture, discontinuous geological formations, and high temperatures (Wilson and Larsen 1998). The species was probably eliminated from most of British Columbia during the last ice age. The northern limit of current distribution probably represents the extent of successful recolonization of suitable habitat (Lynch 1984).
 
Authors / Contributors
Global Information Author: Hammerson, G.
Last Updated: Feb 22, 1996
Provincial Information Author: Penny Ohanjanian and S. Cannings
Last Updated: Mar 17, 2005
   
References and Related Literature
1998. Coeur d'Alene Salamander. B.C. Minist. Environ., Lands and Parks, Wildl. Branch. 2pp.
British Columbia Ministry of Water, Land and Air Protection. 2004. Coeur d'Alene Salamander in Accounts and measures for managing identified wildlife. British Columbia Ministry of Water, Land and Air Protection, Victoria, BC. 52pp.
COSEWIC. 2007c. COSEWIC assessment and update status report on Coeur d'Alene Salamander Plethodon idahoensis in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vi + 22 pp.
Highton, R., and A. Larson. 1979. The genetic relationships of the salamanders of the genus Plethodon. Systematic Zoology 28:579-599.
Howard, J. H., L. W. Seeb, and R. Wallace. 1993. Genetic variation and population divergence in the Plethodon vandykei species group (Caudata: Plethodontidae). Herpetologica 49:238-247.
Nussbaum, R.A., E.D. Brodie, Jr., and R.M. Storm. 1983. Amphibians and Reptiles of the Pacific Northwest. University Press of Idaho, Moscow, Idaho. 332 pp.
Ohanjanian, I.A. 2001. The Coeur d'Alene Salamander in southeastern British Columbia: results of field surveys. Rep. to Habitat Conservation Trust Fund and B.C. Minist. Water, Land and Air Prot., Nelson, BC.
Ohanjanian, I.A. 2001b. The Coeur d'Alene Salamander (P. idahoensis) at the Kuskonook mine - population parameters and salamander characteristics. Rep. to B.C. Minist. Water, Land and Air Prot. and Habitat Conservation Trust Fund.
Ohanjanian, I.A., and I. Teske. 1996. The Coeur d'Alene Salamander in southeastern British Columbia. Rep. to the B.C. Minist. Environ., Lands and Parks. 43pp.
Ovaska, K, S. Lennart, C Engelstoft, L. Matthias, E. Wind and J. MacGarvie. 2004. Best Management Practices for Amphibians and Reptiles in Urban and Rural Environments in British Columbia. Ministry of Water Land and Air Protection, Ecosystems Standards and Planning, Biodiversity Branch
Stebbins, R. C. 1985a. A field guide to western reptiles and amphibians. Second edition. Houghton Mifflin Company, Boston, Massachusetts. xiv + 336 pp.
Wilson, A. G., E. Simon, and J. H. Larsen, Jr. 1989. Range extension for the Coeur d'Alene salamander, Plethodon vandykei idahoensis, to the Canada-United States border. Canadian Field-Nat. 103:93-94.
 

Please visit the website Conservation Status Ranks for definitions of the data fields used in this summary report.

Suggested Citation:

B.C. Conservation Data Centre. 1996. Species Summary: Plethodon idahoensis. B.C. Minist. of Environment. Available: https://a100.gov.bc.ca/pub/eswp/ (accessed Oct 3, 2026).