Allegheny Mountain Dusky Salamander (Desmognathus ochrophaeus)
Other names: mountain dusky salamander, Allegheny dusky salamander
The Allegheny mountain dusky salamander is grey to brown in colour with mottling on the sides. This species often has a light stripe down the back with a row of dark, chevron-shaped spots down the middle, which become less apparent with age. The underside ranges from dark brown to black. As in all dusky salamander species, a pale line runs diagonally from the eye to the jaw, and the hind legs are larger than the front legs. This species is also heavier bodied than other lungless salamanders, such as the eastern red-backed salamander. Adults attain lengths of up to 10 centimetres.
The Allegheny mountain dusky salamander can be easily confused with the northern dusky salamander, which lacks the chevron-shaped dorsal spots. The tail of the northern dusky salamander is laterally compressed at the base rather than rounded. The Allegheny mountain dusky salamander can be differentiated from all other lungless salamanders in Ontario (eastern red-backed, two-lined and four-toed) by the line running from the eye to the back of the jaw, the heavier body and hind legs that are larger than the front legs.
The Allegheny mountain dusky salamander inhabits the mountainous regions of eastern North America from extreme southern Quebec and southern Ontario south to northern Georgia. In Canada, this species is known to occur only at one site in Quebec and in a small portion of the Niagara Gorge in Ontario.
The Allegheny mountain dusky salamander inhabits mountain springs, seepages and small headwater streams in forested areas. Although it actively forages on the forest floor, this species is rarely found far from its aquatic habitat. Subterranean retreats and cover objects such as rocks, logs, moss and leaf litter are important microhabitats that this salamander uses for foraging, nesting and avoiding desiccation and predators. It overwinters in underground retreats or in streams, where it may remain active throughout the winter.
Allegheny mountain dusky salamanders belong to the “lungless” salamander family; they do not have lungs but breathe directly through their skin, which must remain moist to facilitate breathing. They breed on land in the spring or fall and have elaborate courtship rituals. The female deposits 10 to 30 eggs under logs, moss or rocks along stream edges in areas where the soil is saturated with water, and remains with the eggs to protect them from predation and desiccation until they hatch six to 10 weeks later. The aquatic larvae, which are about 1.5 centimetres long when they hatch, metamorphose into semi-terrestrial adults after about one year. They reach sexual maturity at 3 to 4 years of age when they have reached a snout-to-vent length of about three centimetres, and may live up to 15 years. Allegheny mountain dusky salamanders forage primarily at night to avoid desiccation, and eat a variety of aquatic and terrestrial invertebrates.
Threats & Trends
The Allegheny mountain dusky salamander relies on clean headwater streams. Pollution from urban, agricultural or industrial areas is a significant threat to this species. Changes to the groundwater table or stream flow can have significant negative impacts on salamander populations by causing the loss of aquatic habitat, bank instability from excess runoff, or changes to the moisture regimes of terrestrial habitats. Forestry activities can also degrade aquatic habitat by causing siltation of streams, as well as alter the microhabitat conditions of the forest floor. The Ontario population of the Allegheny mountain dusky salamander is especially susceptible to extirpation due to changes in water quality or quantity, since the population relies on a single seepage. This species is rare in Ontario, where it is at the northern limit of its range, and trends in this species’ population levels and distribution are unknown.
Current Status & Protection
The Allegheny mountain dusky salamander is currently listed as Endangered under the Ontario Endangered Species Act, 2007 and Endangered under the federal Species at Risk Act. These acts offer protection to individuals and their habitat. The habitat of this species is further protected in Ontario by the Provincial Policy Statement under the Planning Act. The International Union for Conservation of Nature lists the global status of the Allegheny mountain dusky salamander as Least Concern. The species’ status was confirmed in May 2011. Additional detail about legal protection for species at risk in Ontario is available on our Legal Protection page.
Learn more about reptile and amphibian conservation and what you can do to help these species on our Reptile and Amphibian Stewardship page.
Ontario range (click to enlarge)