Species Profile

Northern Dusky Salamander Carolinian population

Scientific Name: Desmognathus fuscus
Taxonomy Group: Amphibians
Range: Ontario
Last COSEWIC Assessment: May 2012
Last COSEWIC Designation: Endangered
SARA Status: Schedule 1, Endangered


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Quick Links: | Description | Habitat | Biology | Threats | Protection | National Recovery Program | Documents

Image of Northern Dusky Salamander

Description

The Northern Dusky Salamander (Desmognathus fuscus)is a member of the family Plethodontidae (lungless salamanders). Adults are usually brownish with a light dorsal stripe that continues onto the first portion of the tail. The body is sparsely covered with dark spots that are concentrated on the sides and becomes white or grey on the underside. Old individuals tend to be uniformly dark brown or black. Younger life stages have five to eight pairs of dorsal blotches or spots. Both adults and larvae have larger hind legs than forelegs and a pale line extending from the eye to the rear of the jaw. The Northern Dusky Salamander is the most widespread representative of its genus in Canada. (Updated 2017/08/30)

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Distribution and Population

The Northern Dusky Salamander is distributed throughout the mountainous regions of eastern North America. The Canadian distribution accounts for about 5% of the global range and includes a small area in the Niagara Gorge in Ontario, three large areas in Quebec (the Adirondack Piedmont, the Appalachian uplift, and the north shore of the St. Lawrence River), and scattered areas in southern New Brunswick. Within its range, the Northern Dusky Salamander occurs discontinuously usually in high elevation, low-order streams, in forested habitat. There are two designatable units, the Carolinian DU in Ontario, and the Quebec/New Brunswick DU. (Updated 2017/08/30)

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Habitat

The Northern Dusky Salamander inhabits the vicinity of springs, seepages, and small tributaries of clear headwater streams in forested habitats. The species takes refuge under protective cover (rocks, logs, moss or leaf litter) or in cool subterranean retreats near stream edges. It forages along the streamside, mostly in terrestrial habitat. Females usually nest in cryptic microhabitats near a stream’s source where soil is saturated. Larvae are strictly aquatic and remain in interstitial spaces among rocks of the streambed during their development. In winter, larvae remain in shallow running water, whereas adults retreat to subterranean refuges with constant water flow. Habitat availability and quality are optimal in undisturbed watersheds with abundant forest cover. (Updated 2017/08/30)

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Biology

The Northern Dusky Salamander has a biphasic life cycle that includes an aquatic larval stage of 7 to 16 months, followed by a semi-aquatic adult stage. Sexual maturity is attained at 3 to 4 years of age. Mating takes place in the spring or fall and females lay eggs annually in late spring and summer. Fecundity increases with body size, and clutch size varies geographically between 8 and 45 eggs. Females remain with their clutches until they hatch 45 to 60 days after oviposition. Maximum life span is about 10 years. Northern Dusky Salamanders are particularly vulnerable to water loss, and are most active at night. The threat of desiccation makes the species a poor overland disperser. Movements occur primarily along the stream channel usually within a few metres of water’s edge. Adult home range is small (0.1 m² - 3.6 m²). The species consumes aquatic and terrestrial invertebrates opportunistically. It lacks defence mechanisms against predators, but is capable of tail breakage. Fish, snakes, crayfish, birds, small mammals and larger salamanders are the main predators of the Northern Dusky Salamander. Hybridization between Northern Dusky Salamanders and Allegheny Mountain Dusky Salamanders occurs infrequently. (Updated 2017/08/30)

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Threats

Changes in water supply and quality due to human activities are the main threats to the Northern Dusky Salamander in Canada. Decreased groundwater supply to the species’ habitat can be catastrophic to local populations. Artificial increase in discharged water volumes in some areas is also likely to disrupt salamander populations and reduce suitable microhabitats. Runoff water from urban, industrial and agricultural areas can contaminate groundwater and waterways. Heavy metal contamination from atmospheric deposition is likely responsible for the disappearance of the species in Acadia National Park in Maine. Stream acidification is also a concern to the species as nearly 40% of the mountain streams in the southern Appalachians show signs of acidification. Timber harvesting, windfarms, and watershed urbanization reduce water supply, water quality and microhabitat availability. Siltation is one of the most adverse effects of timber harvesting because interstitial spaces used by salamanders for foraging, shelter, nesting, and overwintering are lost. At the watershed scale, urbanization has caused the disappearance of the Northern Dusky Salamander in Mount Saint-Hilaire National Park (Quebec) and other areas. Introduction of predatory fish, particularly Brook Trout, is a threat to the species. (Updated 2017/08/30)

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Protection

Federal Protection

The Northern Dusky Salamander, Carolinian population, is protected under the federal Species at Risk Act (SARA). More information about SARA, including how it protects individual species, is available in the Species at Risk Act: A Guide.

Provincial and Territorial Protection

To know if this species is protected by provincial or territorial laws, consult the provinces' and territories' websites.

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Documents

PLEASE NOTE: Not all COSEWIC reports are currently available on the SARA Public Registry. Most of the reports not yet available are status reports for species assessed by COSEWIC prior to May 2002. Other COSEWIC reports not yet available may include those species assessed as Extinct, Data Deficient or Not at Risk. In the meantime, they are available on request from the COSEWIC Secretariat.

6 record(s) found.

COSEWIC Status Reports

  • COSEWIC assessment and status report on the Northern Dusky Salamander Desmognathus fuscus in Canada (2013)

    The Northern Dusky Salamander (Desmognathus fuscus) is a member of the family Plethodontidae (lungless salamanders). Adults are usually brownish with a light dorsal stripe that continues onto the first portion of the tail. The body is sparsely covered with dark spots that are concentrated on the sides and becomes white or grey on the underside. Old individuals tend to be uniformly dark brown or black. Younger life stages have five to eight pairs of dorsal blotches or spots. Both adults and larvae have larger hind legs than forelegs and a pale line extending from the eye to the rear of the jaw. The Northern Dusky Salamander is the most widespread representative of its genus in Canada.

Response Statements

  • Response Statement - Northern Dusky Salamander, Carolinian population (2013)

    This species is restricted to one small creek sustained by groundwater seepage on the steep slope of a gorge vulnerable to erosion, atmospheric deposition of pollutants and habitat acidification. The population is small and susceptible to ecological, demographic and genetic stochasticity.

Orders

  • Order Acknowledging Receipt of the Assessments Done Pursuant to Subsection 23(1) of the Act (2016)

    His Excellency the Governor General in Council, on the recommendation of the Minister of the Environment, acknowledges receipt, on the making of this Order, of assessments conducted under subsection 23(1) of the Species at Risk Act by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) with respect to the species set out in the annexed schedule.
  • Order Amending Schedule 1 to the Species at Risk Act (2017)

    Biodiversity is rapidly declining worldwide as species become extinct. Today’s extinction rate is estimated to be between 1 000 and 10 000 times higher than the natural rate. Biodiversity is positively related to ecosystem productivity, health and resiliency (i.e. the ability of an ecosystem to respond to changes or disturbances), and, given the interdependency of species, a loss of biodiversity can lead to decreases in ecosystem function and services (e.g. natural processes such as pest control, pollination, coastal wave attenuation, temperature regulation and carbon fixing). These services are important to the health of Canadians, and also have important ties to Canada’s economy. Small changes within an ecosystem resulting in the loss of individuals and species can therefore result in adverse, irreversible and broad-ranging effects. List of Wildlife Species at Risk (referral back to COSEWIC) Order

COSEWIC Annual Reports

  • COSEWIC Annual Report - 2011-2012 (2012)

    Under Canada’s Species at Risk Act (SARA), the foremost function of COSEWIC is to “assess the status of each wildlife species considered by COSEWIC to be at risk and, as part of the assessment, identify existing and potential threats to the species”. COSEWIC held two Wildlife Species Assessment Meetings in this reporting year (September 1, 2011 to September 30, 2012) from November 21 to 25, 2011 and from April 29 to May 4, 2012. On February 3, 2012, an Emergency Assessment Subcommittee of COSEWIC also assessed the status of the Tri-colored Bat (Perimyotis subflavus), the Little Brown Myotis (Myotis lucifugus), and the Northern Myotis (Myotis septentrionalis). During the current reporting period COSEWIC assessed the status or reviewed the classification of 67 wildlife species. For species already found on Schedule 1 of SARA, the classification of 32 species was reviewed by COSEWIC and the status of the wildlife species was confirmed to be in the same category (extirpated - no longer found in the wild in Canada but occurring elsewhere, endangered, threatened or of special concern). The wildlife species assessment results for the 2011-2012 reporting period include the following: Extinct: 1 Extirpated: 4 Endangered: 29 Threatened: 10 Special Concern: 15 Data Deficient: 2 Not at Risk: 6 Total: 67 Of the 67 wildlife species examined, COSEWIC reviewed the classification of 49 species that had been previously assessed. The review of classification for 26 of those species resulted in a confirmation of the same status as the previous assessment (see Table 1a).

Consultation Documents

  • Consultation on Amending the List of Species under the Species at Risk Act: Terrestrial Species – December 2012 (2013)

    As part of its strategy for protecting wildlife species at risk, the Government of Canada proclaimed the Species at Risk Act (SARA) on June 5, 2003. Attached to the Act is Schedule 1, the list of the species that receive protection under SARA, also called the List of Wildlife Species at Risk. Please submit your comments by March 4, 2013, for terrestrial species undergoing normal consultations and by October 4, 2013, for terrestrial species undergoing extended consultations. Consultation paths.