Larch Mountain salamander (Plethodon larselli)

Closeup of a Larch Mountain salamander on mossy ground; a dull-orange stripe shows along its back, from head to tail.
Note the dorsal stripe (yellow in this case) from head to tail on this adult. (William Leonard)
Category: Amphibians
State status: Sensitive
Vulnerability to climate change (More details)

Moderate-
High

If you see this species, please share your observation using the WDFW wildlife reporting form. Providing detailed information such as a photo and exact coordinates will improve the confidence and value of this observation to WDFW species conservation and management.

Photo submission: it is helpful to include photos of the salamander’s topside, underside, and sideview, plus a close-up photo of the rear outer toe.

The Larch Mountain salamander is a small, lungless salamander found only in Washington and Oregon. This species was listed as a Washington state "sensitive" species in 1993 based on their rarity, specific habitat requirements, and need for a comprehensive approach to protect their habitat. They are primarily associated with talus and other rocky habitats although in some areas the association is with older forest types. Being lungless, they depend on their skin for respiration (inhalation and exhalation of air), and they require moist conditions.

Any ground-disturbing activity or land use that changes the moisture regimes and permeability of inhabited rocky substrates, such as over-story tree removal and gravel removal, may threaten populations. In addition, they are small and cannot move very far. These factors all hinder dispersal and colonization to new areas and limits gene flow between populations.

Description and Range

Physical description

The Larch Mountain salamander is a small, striped salamander (less than 2 inches snout to vent length) and 4.33 inches total length. The color on the sides is black or dark brown with white speckling and there may be flecks of the dorsal (topside) stripe color. The dorsal stripe is reddish, yellowish, brown, or tan, and has a scalloped edge and extends to the tip of the tail. The underside is characteristically salmon-pink, red, or reddish orange but a small number of individuals have white or gray undersides. In some adults, with age, the stripe becomes obscured by the large amount of dark pigmentation.

The outer toe on the hind foot has only one segment (phalanx). The costal groove count ranges between 14 and 16 but is usually 15.

The presence of the nasolabial grooves (nose to mouth indentations) separates Lungless Salamanders from other types of salamanders.

The Woodland Salamanders (Plethodon species) in Washington are similar in general appearance. The following traits distinguish the Larch Mountain salamander: 1) the underside is pinkish or red, 2) the dorsal stripe has a scalloped edge with dark pigmentation in a herringbone configuration, 3) there is dense white flecking on the intercostal folds but not in the costal grooves, 4) the stripe typically ends at the base of the head and, 5) the outer toe on the hind foot is a quarter the size of the fourth toe.

The traits listed above for adults are often lacking, subtle or difficult to see in small juvenile Larch Mountain salamanders and they can be easily confused with western red-backed salamanders. However, juvenile Larch Mountain salamanders usually have some reddish pigment blotches or flecks on the belly.

There is no free-living larval stage of Larch Mountain salamander; hatchlings emerge as fully formed miniature versions of the adults. Coloration in juveniles is similar to adults, but the dorsal stripe is more even-edged with brighter coloration and the red pigmentation on the belly tends to be limited to single or multiple blotches or flecks.

For more details about Larch Mountain salamander, see the Washington Herp Atlas.

Ecology and life history

Larch Mountain salamanders are associated with talus, scree, gravelly soils and other areas of accumulated rock where spaces exist between the rock and soil. This species inhabits a diverse range of forested and non-forested habitats.

Close up of a Larch Mountain salamander on a rock surface.
Adult Larch Mountain salamander with a red dorsal stripe - found in Skamania County. William Leonard

Occupied rocky substrates in non-forested areas are usually north facing, and nonvascular plants, especially mosses, dominate the ground cover. In some areas of the Cascade Mountains, Larch Mountain salamanders inhabit old-growth coniferous forests without significant exposed rocky areas. They also inhabit lava tubes in the Mount St. Helens vicinity.

Important microhabitats include woody debris, leaf litter, and/or rocks.

Larch Mountain salamanders are lungless and depend on their moist skin surfaces for oxygen uptake. They spend most of their lives in the subterranean environment, only being surface-active about 20 to 90 days per year. Surface activity is triggered whenever moisture and temperature regimes are appropriate, primarily in the spring and fall.

Breeding takes place in the autumn and spring months. No nests have been found. Development of larvae takes place in the egg, and there is no free-living aquatic larval stage.

Sexual maturity is reached at 3 to 3.5 years for males and 4 to 4.5 years for  females. Larch Mountain salamanders are predators on a variety of invertebrates.

The movements are poorly documented, but home ranges tend to be only 10 to 100 feet in diameter. 

Geographic range

The Larch Mountain salamander is native to Washington and northern Oregon. The main distribution is along a 34-mile stretch of the Columbia River Gorge in southern Washington and northern Oregon, and discontinuously northward in the Cascades in the Snoqualmie Pass-Kachess Lake area.

This map from the Washington Herp Atlas illustrates the known distribution of the Larch Mountain salamander in Washington as of 2016. If you see this species in areas that are not indicated on the map, please share your observation using the WDFW wildlife reporting form.

Larch Mountain Salamander state distribution map:King,Pierce,Lewis,Cowlitz,Clark,Skamania,Klicktat,Kittitas
Western Herp Atlas (2017)

For maps of range-wide distribution and conservation status of this species, check out NatureServe Explorer and the International Union for the Conservation of Nature Red List

Climate vulnerability

Sensitivity to climate change

Moderate-
High

Larch Mountain salamanders are suspected to be sensitive to climate change because of their specialized habitat requirements that include moist talus and rocky areas and the fact that they are limited to below ground retreats unless surface conditions are moist and air temperatures are moderate. Therefore, longer periods of warmer and drier conditions could reduce the window for surface activity and dispersal. Direct mortality from dry conditions are unlikely to occur unless the conditions are so extreme that the below ground retreats completely dry. Little is known about the conditions below ground and, therefore, this vulnerability. Climate change conditions that result in increased rainfall could be beneficial to the species by increasing the window when surface activity is possible but too much rain might compromise the subterranean microhabitats.

Confidence: Moderate

Exposure to climate change

Moderate

  • Increased temperatures
  • Changes in precipitation
  • Changes in talus mobility linked to changes in precipitation
     
Confidence: Moderate

Regulations

Licenses and permits

Be advised that collection of this species is only permitted under a WDFW Scientific Collection Permit for research and educational activities.

Conservation

This species is identified as a Species of Greatest Conservation Need (SGCN) under the State Wildlife Action Plan (SWAP). SGCN-classified species include both those with and without legal protection status under the Federal or State Endangered Species programs, as well as game species with low populations. The WDFW SWAP is part of a nationwide effort by all 50 states and five U.S. territories to develop conservation action plans for fish, wildlife and their natural habitats—identifying opportunities for species' recovery before they are imperiled and more limited.
This species is identified as a Priority Species under WDFW's Priority Habitat and Species Program. Priority species require protective measures for their survival due to their population status, sensitivity to habitat alteration, and/or recreational, commercial, or tribal importance. The PHS program is the agency's main means of sharing fish and wildlife information with local governments, landowners, and others who use it to protect priority habitats for land use planning.

Conservation Threats and Actions Needed

  • Resource information collection needs
    • Threat: Lack of information on status and distribution.
    • Action Needed: Continue research, surveys and monitoring to understand species distribution and status.
  • Fish and wildlife habitat loss and degradation
    • Threat: Removal of trees. This small, non-vagile (non-dispersing) species needs cool, moist conditions.
    • Action Needed: Prevent habitat modification at sites occupied by Larch Mountain salamanders.
  • Energy development and distribution
    • Threat: Mining of rock and boulders. This small, non-vagile species is closely associated with rock features such as talus.
    • Action Needed: Prevent habitat modification at sites occupied by Larch Mountain salamanders.
  • Climate change and severe weather
    • Threat: Loss of suitable habitat. This small, non vagile species needs moist conditions and is closely associated with rock features such as talus. Surface activity is limited by moisture and temperature.
    • Action Needed: Prevent habitat modification at sites occupied by Larch Mountain salamanders.
    • Threat: Drying of habitat. Surface activity is limited by moisture and temperature (fall and spring). These salamanders are lungless and depend on moist skin surfaces for oxygen uptake.
    • Action Needed: Prevent habitat modification at sites occupied by Larch Mountain salamanders.
    • Threat: Warming and drying of habitat. This small, non-vagile species needs moist conditions. Surface activity is limited by moisture and temperature (fall and spring). These salamanders are lungless and depend on moist skin surfaces for oxygen uptake.

See Climate vulnerability section above for more information about the threat posed by climate change to Larch Mountain salamanders.

Conservation Efforts

WDFW has partnered with the U.S. Forest Service to conserve Larch Mountain salamanders. Nothing is known about population trends in this species. Surveys were conducted at 825 forested sites from 1996 to 2002, with individuals detected at only 55 (6.7%) locations. Observations suggest that Larch Mountain salamanders are patchily distributed but locally abundant at a number of sites in the Columbia River Gorge and Washington Cascades. In 2008, there were 145 known locations, with 103 on federal lands and 42 on non-federal lands; most of the sites are in Washington. About 70% of currently known sites on federal lands occur in areas with special management designations, such as late seral reserves.

Regarding geographic variation and genetic structure, DNA analysis has indicated there was substantially less differentiation among populations of Larch Mountain salamanders in Washington than in populations in Oregon. The Columbia River provides a long-term barrier indicating that populations are currently on separate evolutionary trajectories. They suggested that distinct management strategies for northern versus southern populations may be appropriate.

Resources

References

Crisafulli, C. M., D. R. Clayton, and D. H. Olson. 2008. Conservation assessment for the Larch Mountain salamander (Plethodon larselli). Version 1. USDA Forest Service Region 6, and USDI BLM, Interagency Special Status and Sensitive Species Program. 36 pp.

Hallock, L. A. and K. R. McAllister. 2005. Larch Mountain Salamander. Washington Herp Atlas. 2009. A cooperative effort of Washington Natural Heritage Program, Washington Department of Fish and Wildlife, U.S.D.I. Bureau of Land Management, and U.S. Forest Service. Map products updated March 2017. Provisional PDF version of the website (2005-2019) created July 2019. 250 pp.  

NatureServe. 2014. Larch Mountain Salamander. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://explorer.natureserve.org. (Accessed: November 13, 2014).

Petranka, J. W. 1998. Salamanders of the United States and Canada. Smithsonian Institutional Press, Washington. 587pp.

Wagner, R. S., M. P. Miller, C. M. Crisafulli, and S. M. Haig. 2005. Geographic variation, genetic structure, and conservation unit designation in the Larch Mountain salamander (Plethodon larselli). Canadian Journal of Zoology 83: 396–406.

WDFW publications 

PHS Program

Status reports

WDFW educational resources

Other resources