Coeur d’Alene Salamander

Coeur d' Alene Salamander, FOC Photo

(Plethodon idahoensis)

Physical Characteristics: A small, slender salamander reaching 2-4 inches in length; grayish-black ground color with a dorsal stripe of yellow or gold running the length of the body, and a yellow patch on the throat. The two forelimbs have four short toes each; the hind legs have five toes each. This organism is part of the Plethodontidae salamander family, defined by a lack of lungs. Breathing is done through the skin and tissues lining the mouth. Another distinctive feature is a vertical slit between the nostril and upper lip known as the naso-labial groove. This groove is lined with glands that enhance the salamander’s reception of chemical stimuli in its environment.

Diet: The salamander feeds on invertebrates: insects, millipedes, mites, spiders, snails, and segmented worms.

Habitat: This salamander is found in 3 major types of habitat: springs or seepages, spray zones of waterfalls, and edges of streams. Often associated with fractured rock formations. The slippery critter prefers moist talus, seep, and splash zones, which may be situated in open forest, meadows, or riparian areas; generally well-shaded, north-facing slopes. In wet weather it also slinks in leaf litter and under bark and logs in coniferous forests. Coeur d’Alene Salamander eggs are deposited terrestrially, which may presumably be found in similar habitat under rock or ledge, though no nest sites have been found in the wild.

Range: While some instances of capture or sightings of the species occurred in western Montana and southeastern British Columbia, the majority is localized in northern Idaho. Specifically, the St. Joe and North Fork Clearwater basins, and the Selway, Moyie, and Kootenai river drainages. Due to a lack of research and rarity of sightings and/or capture, population trend data for the Coeur d’Alene Salamander is incomplete. What research has been done shows that the Clearwater populations are more genetically diverse and unique. There are three genotypes for the species, one in the Selway, one in the Lochsa, and one from the North Fork Clearwater/elsewhere. This suggests that the species was limited by glaciation to the Clearwater Basin during the last ice age, and the populations in and around the North Fork Clearwater repopulated the areas to the north after glacial retreat.

Reproduction: Generally, Coeur d’Alene Salamanders mate above ground in late summer and fall, and to a lesser extent, in spring. After a courtship ritual of an hour or more, the male deposits sperm which the female then picks up and stores for up to nine months before fertilizing and depositing her eggs. The eggs are an un-pigmented, grape-like cluster of about six on a single thread. The young emerge from underground in September, and reach sexual maturity in their fourth or fifth year. Males breed every year, but females have a biennial reproductive cycle.

Threats: Populations continue to be vulnerable to highway construction, especially at elevations, and in forest types where timber harvest is common. Population monitoring and data is spotty at best, and needs to be done more thoroughly, as both a regional amphibian-monitoring program, and as part of habitat protection and water quality efforts. The Coeur d’Alene Salamander is listed as a Sensitive Species in both Idaho and Montana.

Miscellaneous: The species was named after the lake where it was discovered in 1939. Since Coeur d’Alene Salamander breathes through its skin, it is susceptible to moisture loss through evaporation and therefore restricted to a cool, damp environment. Generally these salamanders only come above ground during the night when the temperature is above 45 degrees F, and to feed on the invertebrates that are also nocturnal. The species emerges from winter hibernation in late March and is active near the surface through April and May; surface activity is negatively correlated with daytime temperatures and number of days since the last rain. From June until mid-September, the creatures retreat to the cool underground to aestivate–a state of dormancy where the body is inactive and the metabolic rate drastically lowers in response to high temperatures and arid conditions. Aestivating helps the Coeur d’Alene Salamander avoid drying out and being damaged from high temperatures.







Comments are closed.