Cascade torrent salamander (Rhyacotriton cascadae)

Close up of a Cascade torrent salamander on a mossy rock
Torrent salamanders have a short, rounded snout and generally prominent yellow colored belly.   (W.P. Leonard, Copyright)
Category: Amphibians
Family: Rhyacotritonidae - Torrent salamanders
Ecosystems: Riparian areas
State status: Candidate
Vulnerability to climate change (More details)

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.

This salamander is sensitive to temperature variation and increased sedimentation that may be caused by disturbances, such as logging and road construction.

Some populations of Cascades torrent salamander are isolated by surrounding areas of unsuitable habitat and are vulnerable to extirpation through stochastic events exacerbated by habitat loss. Temperature sensitivity and limited dispersal ability makes this species potentially sensitive to climate change.

Description and Range

Physical description

This is a small salamander that rarely exceeds 2.25 inches in length from snout to vent. The body is relatively long with short limbs and a short tail. The head is small with a short, rounded snout. Coloration is brown above and yellow to orange-yellow below. White speckling on the body appears mainly on the sides. Dark spots occur on the back and some on the belly. Varying amounts of dark dorsal spotting or mottling are a prominent feature of the color pattern, and a few black spots are often present on the belly. 

Cascade torrent salamanders have large prominent eyes. The large size of the eyes (eye diameter approximately equal to snout length), relatively short rounded snout and generally prominent yellow component to the belly color are features that help distinguish torrent salamanders from other Washington salamanders.

Adult male torrent salamanders can be distinguished from all other salamanders by the presence of prominent squared vent lobes, a trait unique to the family and the genus.

The color pattern and morphology of torrent salamander species are similar and variable; therefore, torrent salamander species are best identified by collection locality and how that relates to the documented ranges of each species.

Superficially, metamorphosed torrent salamanders resemble woodland salamanders (Plethodon species) and ensatina, but torrent salamanders lack nasolabial grooves and a constriction at the base of the tail (unique to ensatina). Torrent salamanders and rough-skinned newts have a similar color pattern, but differ in overall appearance with newts being stockier, having a thicker skin that is often rough (in the terrestrial phase) and lacking costal grooves.

Adult torrent salamanders have very reduced lungs and breathe mostly through their skin.

Larvae 

Torrent salamander larvae have well-developed functional limbs, prominent dorsally positioned eyes that do not greatly protrude, and a white (young larvae) to yellow-orange belly. Torrent salamander larvae are the only stream-adapted larval salamanders in Washington with a yellow to orange belly; stream-adapted salamanders have small gills and reduced tail fin.

Eggs

Eggs have not been found in the wild, suggesting females hide them well, perhaps in fractured rock or deep in springs. As in other members of the genus, eggs are thought to be unpigmented, laid singly and not attached to the substrate.

For more details about Cascade torrent salamander, see the Washington Herp Atlas.

Ecology and life history

This species is generally found in high-gradient, cold streams, seepages and waterfall splash zones, typically in areas with a thick canopy cover. Interestingly however, this species survived in many sites that were completely deforested by the 1980 eruption of Mount St. Helens. They usually occur in stream segments or off-channel habitats, such as seeps and waterfall splash zones, that are shallow, slow flowing and that have gravel or rock rubble that is silt-free. Adults are strongly associated with water and individuals are almost always found in contact with either free water or saturated substrates. During rainy wet periods individuals may be found in wet terrestrial forest settings away from streams or seepages.

Cascade torrent salamanders may be active year-round at lower elevations.

Breeding phenology is unknown, but may occur during most of the warmer months of the year. Eggs are most likely laid in the spring. The first described Cascade torrent salamander nest was found on 14 August 2003 in a second-order headwater stream on the west slope of the Cascade Mountains in Skamania County under a cobble-sized rock in the middle of a calm stretch of the stream channel 4 inches deep by 24 inches wide by 28 inches long. This differs from other Rhyacotriton species that are described as laying eggs in deep cracks and crevices of springs and seeps. The nest contained five eggs that were not attached to the substrate or each other.

The larval period is thought to be long; a Columbia Gorge population was estimated to require four to five years before metamorphosis.

Geographic range

In Washington, this species ranges from the west slopes of the Cascade Mountains south of Nisqually River to the Columbia River. Distribution is patchy. They can reach high densities in optimal habitat.

This map from the Washington Herp Atlas illustrates the known distribution of the Cascade torrent salamander in Washington as of 2016.

Cascade torrent salamander distribution map of Washington as of 2016: detections in Lewis, Clark, Cowlitz, Skamania counties
Washington Herp Atlas (2017)

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

Climate vulnerability

Sensitivity to climate change

High

Cascade torrent salamanders are likely highly sensitive to climate change due to their deposition on unattached eggs in low flow habitats, their inability to tolerate desiccation and specialized habitat requirements. Declines in water availability and timing (e.g., due to reduced snowpack and earlier snow melt), as well as increased sedimentation (e.g., due to shifts from snow to rain), could decrease suitable headwater habitat for this species. Increases in the seasonal rainfall, especially that which results from extreme events from atmospheric rivers has the potential to blow out oviposition or rearing sites. This species may also be physiologically limited by high temperatures.

Confidence: Moderate

Exposure to climate change

High

  • Increased temperatures (air and water)
  • Changes in precipitation
  • Reduced snowpack
  • Shifts from snow to rain
  • Earlier snowmelt
  • Changes in stream discharge (altered hydrology) Again, if one is interested in order of importance, changes in precipitation and discharge (stream hydrology) should probably precede the balance here

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: Increase in water temperatures and sedimentation. This species is closely associated with cool forested streams.
    • Action Needed: Leave suitable forest buffers on occupied streams to prevent water temperature increases and sedimentation.
  • Climate change and severe weather
    • Threat: Direct mortality and loss of micro-habitat features due to stream flooding, erosion and scouring.
    • Action Needed: Leave refuge areas of intact habitat. Buffered streams in clear cuts are more likely to be impacted by extreme precipitation and wind events.
    • Threat: Stream and seep drying. This species is closely associated with cool, forested streams.
    • Action Needed: Minimize habitat fragmentation and maintain robust populations across landscape.
    • Threat: Loss of suitable habitat. This species is closely associated with cool, forested streams and is dependent on specific microhabitat features.
    • Action Needed: Minimize habitat fragmentation and maintain robust populations across landscape.
    • Threat: Warming and drying of streams. his species is closely associated with cool, forested streams.
    • Action Needed: Minimize habitat fragmentation and maintain robust populations across landscape. 

See the Climate vulnerability section for more information about threats posed by climate change to this species.

Resources

References

Jones, L. L. C., W. P. Leonard, and D. H. Olson, editors. 2005. Amphibians of the Pacific Northwest. Seattle Audubon Society, Seattle, Washington. xii + 227pp.

Leonard, W. P., H. A. Brown, L. L. C. Jones, K. R. McAllister and R. M. Storm. 1993. Amphibians of Washington and Oregon. Seattle Audubon Society The Trailside Series, Seattle, Washington. 169 pp.

MacCracken, J.G. 2004. Rhyacotriton cascadae (Cascade Torrent Salamander) Nest. Herpetological Review 35(4): 367.

Nijhuis, M. J. and R. H. Kaplan. 1998. Movement patterns and life history characteristics in a population of the Cascade Torrent Salamander (Rhyacotriton cascadae) in the Columbia River Gorge, Oregon. Journal of Herpetology 32(2): 301-304.

Nussbaum, R. A., E. D. Brodie, Jr., and R.M. Storm. 1983. Amphibians and Reptiles of the Pacific Northwest. University of Idaho Press, Moscow, Idaho. 332 pp.

Nussbaum, R. A. and C. K. Tait. 1977. Aspects of the life history and ecology of the Olympic Salamander, Rhyacotriton olympicus (Gaige). The American Midland Naturalist 98: 176-199.

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

Stebbins, R. C. 1951. Amphibians of Western North America. Univ. of Cal. Press, Berkeley. 539pp.

Welsh, H. H. Jr. and A. J. Lind. 1996. Habitat Correlates of the Southern Torrent Salamander, Rhyacotriton variegatus (Caudata: Rhyacotritonidae), in Northwestern California. Journal of Herpetology 30(3): 385-398.

WDFW publications 

PHS Program

WDFW educational resources

Other resources