Shenandoah Salamander

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Shenandoah Salamander

Plethedon shenandoah

StatusEndangered
ListedAugust 18, 1989
FamilyPlethodontidae (Lungless Salamander)
DescriptionTwo color phases; dark-backed with a few gold flecks or with a narrow red stripe on the back.
HabitatNorth-facing talus slopes.
FoodInsects.
ReproductionEgg masses laid from May to August.
ThreatsCompetition from abundant salamander species.
RangeVirginia

Description

The Shenandoah salamander is one of the lungless salamanders, also known as woodland salamanders. These salamanders lack lungs and must rely on respiratory exchange directly through their skin. Two color phases of this species are known. Individuals of the unstriped phase have dark backs, marked with a few gold or silver flecks, and dark gray to black bellies. Striped phase individuals have a narrow red stripe down their backs. This salamander grows to a length of about 4.6 in (12 cm). It generally has 18 vertical grooves on its sides that mark the position of the ribs.

This species was first described as a subspecies of Plethodon richmondi in 1967 and later considered a subspecies of the Cheat Mountain salamander (P. nettingi. It was recognized as a distinct species in 1979.

Behavior

The Shenandoah salamander generally spends the day under rocks and logs or in rock crevices. At night, particularly in wet weather, it forages for mites, springtails, beetles, flies, and other insects. Although mating has not been observed, it is assumed to be similar to other woodland salamanders. The eggs are fertilized internally and undergo complete development. Unlike most other salamanders there is no aquatic larval stage. Masses of from four to 17 eggs are deposited on logs or moss from May to August.

Habitat

The Shenandoah salamander is found on north-facing talus slopes at elevations above 3,000 ft (915m). It is limited to areas where the moisture conditions are favorable, but can survive in drier areas than other Plethodon species.

Distribution

Because of its recent discovery and limited range, the actual historic range of the Shenandoah salamander is unknown. Because of the species' narrow ecological niche, it is surmised that it was never numerous.

Today the Shenadoah salamander survives on talus slopes on three mountains in Madison and Page counties, Virginia. All three sites are within the boundaries of Shenandoah National Park. There are no current population estimates.

Threats

The major threats to the Shenendoah salamander are thought to be habitat damage caused by the defoliation of trees by introduced insects, and perhaps by acidic precipitation. It may also be suffering from competition with the abundant red-backed salamander (Plethodon cinereus ). The Shenandoah salamander can survive in dryer conditions than the red-backed salamander. However, as the talus slopes disintegrate and organic debris decomposes, moister conditions develop, which favors the red-backed salamander.

Conservation and Recovery

The Fish and Wildlife Service published a Recovery Plan for the Shenandoah salamander in 1994. All of its known critical habitats are protected within Shenandoah National Park. However, there is ongoing habitat damage by introduced pest insects that feed on dominant species of trees. The populations of the Shenandoah salamander should be surveyed more extensively and monitored, and research undertaken into its biology, habitat needs, and beneficial management practices (particularly the control of insect damage).

Contacts

U.S. Fish and Wildlife Service
Office of the Regional Director
Hadley, Massachusetts 01035-9589
Telephone: (413) 253-8308
Fax: (413) 253-8308
http://northeast.fws.gov/

U.S. Fish and Wildlife Service
Chesapeake Bay Ecological Services Field Office
177 Admiral Cochrane Drive
Annapolis, Maryland 21401-7307
Telephone: (410) 573-4500
Fax: (410) 263-2608
E-mail: Laurie_Hewitt@fws.gov
http://www.fws.gov/r5cbfo/index.html

References

Jaeger, R. G. 1970. "Potential Extinction through Competition Between Two Species of Terrestrial Salamanders." Evolution 24: 632-642.

Jaeger, R. G. 1974. "Competitive Exclusion: Comments on Survival and Extinction of Species." Bioscience 24: 33-39.

Jaeger, R. G. 1980. "Density-dependent and Density-independent Causes of Extinction of a Salamander Population." Evolution 34(4): 617-621.

U.S. Fish and Wildlife Service. 1994. "Shenandoah Salamander (Plethodon shenandoah ) Recovery Plan." Hadley, Massachusetts.

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