| Species | Plethodon dunni Bishop |
| Family | Plethodontidae (Lungless Salamanders) |
| Status | State Candidate |
| State Rank | S2S3 |
| Global Rank | G4 |
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A striped salamander reaching sizes of 67 to 75 mm snout-vent length, 139 to 154 mm total length (male to female size respectively). This is Washington's largest Woodland Salamander (Plethodon species). The sides of the body are black or dark brown with white speckling and blotches of pigmentation similar in color to the dorsal stripe. The dorsal stripe is tan, yellow or green and has dark blotches of pigmentation the same color as the sides of the body. The dorsal stripe does not extent to the tip of the tail. The belly is dark with yellow or white flecks. Coloration in juveniles is similar, but the dorsal stripe tends to be brighter with a more even edge. Melanistic individuals have not been found in Washington but do occur in Oregon. Size at sexual maturity is 50-55 mm snout-vent length. There is no free-living larval period. See Photos Page.
The presence of nasolabial grooves separates Lungless Salamanders from other types of salamanders. The Woodland Salamanders (Plethodon species) in Washington are similar in general appearance to each other. The following traits distinguish the Dunn's Salamander: 1) the dorsal stripe of large juveniles and adults does not extend to the tip of the tail and has an uneven, "eroding" edge that is invaded by blotches of the side color, 2) the sides of the body have patchy blotches and flecks similar in color to the dorsal stripe, 3) the costal groove count is usually 15 with 2.5 to 4.0 intercostal folds between adpressed limbs. Contrary to the common name, the Western Red-backed Salamander (Plethodon vehiculum) often has a yellow or tan dorsal stripe. In the Willapa Hills, it is common to find individuals with black pigment invading the dorsal stripe (melanism) resulting in a dorsal stripe that may be absent, fragmented, and/or does not extend to the tip of the tail. Unlike the Dunn's Salamander, however, Western Red-backed Salamanders do not have blotches and flecks of the stripe color on the sides of the body. The Long-toed Salamander has a similar color pattern, but lacks the nasolabial grooves unique to Lungless Salamanders, has a rounded snout and the fourth hind toes are noticeably longer than the rest of the toes. See Key Features Page.
Most surface activity takes place in the spring after snowmelt and before summer drought and in the fall after the onset of fall rains and before temperatures approach freezing. Because this species occupies wet habitats, it is sometimes active even in summer. The reproductive biology of this species is poorly known.
In Washington, this species occurs in the Willapa Hills of the Olympic Physiographic Province. The range extends north to the Chehalis River and east to the Cowlitz River. This is the northern extreme of this species' range. See Distribution Map.
For information on the complete range of this species, see NatureServe Explorer.
All life stages are terrestrial. Dunn's Salamanders are usually associated with streams and seepages in forested habitat. Typically, they occupy the splash zone, where they can be found in bank gravel, under rocks and under woody debris. They also occupy moist talus. During rainy periods when the ground is saturated, they may be found in terrestrial habitats away from water.
The state status is based on the species' limited range within Washington and its primary association with small streams that historically received little or no streamside buffers associated with logging practices.
More information is needed on population dynamics and life history. Seasonal habitat associations could be better described, especially egg-laying habitat characteristics. Research needs include information on the impacts of forestry practices and the importance of large woody debris.
Threats are poorly defined although the condition of riparian corridors is clearly important and should receive continued scrutiny. Removal of large woody debris from streams and terrestrial habitats may also be detrimental.
Dunn’s Salamander Study – This study is a retrospective study that addresses the landscape and local distribution of terrestrial amphibians in timber-managed landscapes. Dunn’s salamander (Plethodon dunni) and Van Dyke’s salamander (Plethodon vandykei), two Forests and Fish Agreement (Ffr) target species, are the focus of the study. A major study focus is the pattern of associated of terrestrial amphibian with woody debris and how that may vary with other landscape and local variables. The study is intended to inform what further adaptive management may be required to address terrestrial amphibians in timber-managed landscapes. Funding is through the Cooperative Monitoring Evaluation and Research (CMER) Committee, the Adaptive Management arm of Ffr, and numerous stakeholders (major and minor private landowners, state and federal agencies, tribes, and an environmental caucus) support this study.
Brodie (1970), Leonard et al. (1993), Nussbaum et al. (1983).
Personal communications: M. Hayes
Hallock, L.A. and McAllister, K.R. 2005. Dunn's Salamander. Washington Herp Atlas. http://www1.dnr.wa.gov/nhp/refdesk/herp/
Last updated: February 2005