Coeur d'Alene salamander

The Coeur d'Alene salamander, Plethodon idahoensis, is a species of woodland salamander (Plethodon) in the family of lungless salamanders (Plethodontidae). This species was discovered in 1939 by James R. Slater and John W. Slipp on the south shore of Coeur d'Alene Lake in Northern Idaho. It was once considered to be a subspecies of Van Dyke's salamander Plethodon vandykei idahoensis, but appears to be a distinct and separate species as originally suggested by Slater and Slipp (1940).

Physiology

P. idahoensis specimens are slender salamanders from two to four inches in length. The adult has a nasolabial groove, parotoid glands, and parasphenoid teeth. Coloration and markings key to characterizing this species include a dark ground color with a yellow-gold dorsal stripe that extends the length of the organism, as well as ventral yellow patches on the throat. The toes of the Coeur d'Alene salamander are shorter than those of the long-toed salamander, which aids in distinguishing the two species.

The eggs of the Coeur d'Alene salamander have a unique physiology, as well. They are not pigmented and occur in grape-like clusters, attached via a single thread.

Similar species

Common name	Binomial name
Central long-toed salamander	Ambystoma macrodactylum columbianum
Dunn's salamander	Plethodon dunni
Larch Mountain salamander	Plethodon larselli
Van Dyke's salamander	Plethodon vandykei idahoensis
Western red-backed salamander	Plethodon vehiculum

Distribution

While the majority of this species is localized in northern Idaho, some instances of capture/sighting in western Montana and southeastern British Columbia have occurred. About 95% of observed populations in Idaho and Montana have been verified extant since 1987; the remainder may have [extirpated], but with a general lack of knowledge on the population trends of the Coeur d'Alene salamander.

The majority of known data has been observed in the St. Joe and North Fork Clearwater River basins, but they also occur in the Selway, Kootenai, and Moyie drainages.

Habitat

The preferred territory of P. idahoensis is in the corridors of stream riparian zones, in the splash zone of waterfalls, near seeps and springs, or in stream-side scree. Specimens are usually associated with fractured rock formations in moist environments, often localized around fresh, moving water.

Lifestyle

Generally, these salamanders only come above ground during the night when the temperature is above 45°F. Coeur d'Alene salamanders are known to eat aquatic insects and other invertebrates, which are also active during the night.

In northern Idaho, P. idahoensis emerges from winter hibernation in late March and is active near the surface through April and May; this surface activity is negatively correlated with both high daytime temperatures and the number of days since last rain. From June until mid-September, Coeur d'Alene salamanders retreat underground to aestivate. A second period of activity continues with September through early November rains, followed by a period of hibernation that lasts until spring.

Reproduction

Clutch size varies from a small cluster (about 4) to 13.

Management issues

Due to lack of research and rarity of sightings/capture, population trend data for the Coeur d'Alene salamander are spotty at best. There are thought to be small sites where the species is abundant and capable of observation, but without an implemented monitoring program, few data are available with which to evaluate population trends. This lack of information puts the Coeur d'Alene salamander on both Idaho's and Montana's Species of Special Concern lists.

Conservation classifications

System	Status
Rangewide	G4 Apparently secure
Statewide	S2 Imperiled
ESA	No status
US Forest Service	Region 1: Sensitive
Bureau of Land Management	Type 3 Regional/State imperiled
Idaho Department of Fish and Game	Protected nongame

References

• "Slater JR and Slipp JW 1940. A new species of Plethodon from Northern Idaho. Occasional Papers, Department of Biology, University of Puget Sound 8: pp 38-43.". Retrieved 2012-02-02. 

• Cassirer EF, Groves CR, Genter DL. August 1994. "Coeur d'Alene Salamander Conservation Assessment". USDA Forest Service, Region 1.

• Wilson AG, Larsen JH Jr. 1988. "Activity and Diet in Seepage-dwelling Coeur d'Alene Salamanders (Plethodon vandykei idahoensis)". Northwest Science, volume 62:5. pp 211-217.

• Wilson AG, Larsen JH Jr. 1998. "Biogeographic Analysis of the Coeur d'Alene Salamander (Plethodon idahoensis)". Northwest Science, volume 72:2. pp 111-115.

• Wilson AG, Wilson EM, Groves CR, Wallace RL. 1997. "US Distribution of the Coeur d'Alene Salamander (Plethodon idahoensis, Slater and Slipp)". Great Basin Naturalist, volume 57:4. pp 359-392.

Web sources

• "Idaho Conservation Data Center". Retrieved 2009-09-25. 

• "California Herps". Retrieved 2009-09-25. 

• "Wildlife of the Idaho Panhandle National Forests". Retrieved 2008-04-05. 

• "AmphibiaWeb". Retrieved 2009-09-25. 

• "Discover Life". Retrieved 2009-09-25. 

Additional reading

• Ohanjanian IA. 2000. "The Coeur d'Alene Salamander (Plethodon idahoensis) in the operating area of Wynndell Box and Lumber Company". Ltd. Ministry of Environment/FRBC report, BC, Canada.