Species Profile

Magnum Mantleslug

Scientific Name: Magnipelta mycophaga
Taxonomy Group: Molluscs
Range: British Columbia
Last COSEWIC Assessment: May 2012
Last COSEWIC Designation: Special Concern
SARA Status: Schedule 1, Special Concern


Go to advanced search

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

Image of Magnum Mantleslug

Description

The Magnum Mantleslug is the sole member of the genus Magnipelta. It is a large slug up to 80 mm in length. Its most distinctive feature is a large mantle, which covers most of the back. The body is tan-brown with uneven black spotting; there is an irregular dark stripe on each side of the mantle. The species is regionally endemic to the northern Columbia Basin and adjacent mountains, an area that contains many unique plants and animals. (Updated 2017/08/11)

Top

Distribution and Population

The Magnum Mantleslug occurs in southeastern British Columbia (BC), northwestern Montana, northern Idaho, and extreme northeastern Washington. About half of the species’ global distribution is in BC; the remainder is mostly in Montana. In BC, the species distribution extends from the Canada – US border north to Wells Gray Provincial Park and from near Trail east to Fernie. This distribution encompasses portions of the Rocky Mountains, Columbia Mountains (Purcell, Selkirk, and Monashee ranges), and Shuswap Highlands. The distribution of the species is extremely patchy within this large range, possibly reflecting the availability of suitable moist habitats and low dispersal abilities of the slugs. As of November 2010, there are 13 records of the species from scattered sites, assigned to nine populations. Hundreds of sites have been searched for slugs and land snails within the distribution of this species, mostly within the past 10 years. (Updated 2017/08/11)

Top

Habitat

The Magnum Mantleslug occupies coniferous forests at mid- to high elevations and requires cool, moist conditions. In BC, the species has been found in Interior Cedar-Hemlock and Engelmann Spruce–Sub-alpine Fir biogeoclimatic zones at elevations of 800 - 2060 m. The slugs inhabit very moist microsites, often with abundant herbaceous vegetation such as found in splash zones of cascading creeks and avalanche chutes, but also occur on the forest floor under heavily shaded forest canopy. The slugs are often associated with decaying logs and other coarse woody debris and have also been found under rocks in stable talus in moist situations. From 1960 to present, habitats of the Magnum Mantleslug in Canada have become increasingly fragmented mainly due to logging, agriculture, ranching, mining, hydro development, transportation corridors and land conversions to residential areas. Considerable areas of mid- to high elevation forests are still intact due to a network of protected areas and inaccessible terrain, but logging and other resource extraction activities continue to expand in higher elevation forests. (Updated 2017/08/11)

Top

Biology

Very little is known of the life cycle of the Magnum Mantleslug. The species is hermaphroditic, possessing both female and male reproductive organs, but exchange of sperm with other individuals, rather than self-fertilization, is probably the norm similar to most other slugs. The slugs lay eggs and can live more than 1 year; whether individuals are capable of reproducing in their first year is unknown but possible. The slugs are active during moist conditions from spring to autumn and seem to prefer substrate temperatures of 12 - 15°C. Their requirements for cool, moist microhabitats probably limit their distribution within the landscape and increase their vulnerability to human activities that alter hydrology or forest floor microclimates. The species is expected to have poor dispersal abilities similar to other terrestrial gastropods. These slugs exhibit an unusual behaviour in response to disturbance. If provoked, the slug is prone to spread its large mantle in a wing-like fashion. This behaviour perhaps startles a predator or exaggerates the slug’s body size, making it appear too large to swallow. (Updated 2017/08/11)

Top

Threats

At known sites, the species is threatened by logging, recreational developments and activities, wildfire, and climate change. Logging is pervasive throughout the species’ range, and five of 10 occupied sites are on forestry lands. Logging alters temperature and moisture regimes on the forest floor and can disturb or destroy habitat patches. Logging roads have increased public access to the backcountry, including off-road vehicle use that compacts soil and can destroy habitat patches used by the slugs. Recreational developments and activities, such as ski hill developments, are localized but expanding within the species’ range. Infrastructure development and heavy recreational use can result in soil compaction and damage to understorey vegetation, posing threats to slug habitats. Strip-mining for coal is expanding in the southeastern part of the species’ range in Canada. The frequency and extent of wildfires is expected to increase with climate change and Mountain Pine Beetle infestations that are sweeping across interior BC. Terrestrial gastropods are thought to be sensitive to fire, which can decimate habitats and individuals, but the ability of the Magnum Mantleslug to survive fire events and persist in burned areas is unknown. Increased mortality due to the toxic effects of fire retardant chemicals is also a potential threat. Climate change is predicted to result in shifts in habitats and ecosystems over the next decades. Species occupying higher elevation habitats, such as the Magnum Mantleslug, might be especially vulnerable to shifts in habitats and ecosystems along altitudinal gradients, but the magnitude of such effects is uncertain. (Updated 2017/08/11)

Top

Protection

Federal Protection

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.

Top

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 Magnum Mantleslug Magnipelta mycophaga in Canada (2013)

    The Magnum Mantleslug is the sole member of the genus Magnipelta. It is a large slug up to 80 millimetres in length. Its most distinctive feature is a large mantle, which covers most of the back. The body is tan-brown with uneven black spotting; there is an irregular dark stripe on each side of the mantle. The species is regionally endemic to the northern Columbia Basin and adjacent mountains, an area that contains many unique plants and animals.

Response Statements

  • Response Statement - Magnum Mantleslug (2013)

    This large slug, up to 80 mm in length, is regionally endemic to the northern Columbia Basin in western North America. About half of the species’ global range extends into southeastern British Columbia. It occurs in a number of widely separated habitat patches and is confined to cool, moist places in coniferous forests at mid to high elevations. While hundreds of sites have been searched for slugs and land snails within the range of this slug, mostly within the past decade, as of November 2010 there are only 13 records for it in Canada. Since the 1960s its habitat has become increasingly fragmented. The number and variety of threats including logging, recreational developments and activities, wildfire, and changes in moisture regimes caused by climate change increase the level of risk.

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 with respect to the species set out in the annexed schedule.
  • Order Amending Schedule 1 to the Species at Risk Act (2017)

    His Excellency the Governor General in Council, on the recommendation of the Minister of the Environment, pursuant to subsection 27(1) of the Species at Risk Act, makes the annexed Order Amending Schedule 1 to the Species at Risk Act.

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.