Species Profile

Nugget Moss

Scientific Name: Microbryum vlassovii
Taxonomy Group: Mosses
COSEWIC Range: British Columbia
COSEWIC Assessment Date and Status Change: November 2016
COSEWIC Status: Endangered
COSEWIC Status Criteria: D1
COSEWIC Reason for Designation: In Canada, this globally rare moss is known from only three localized sites in semi-arid areas of south-central British Columbia. One of the sites is extirpated and another has not been seen since 1980. The moss grows on fine soils on the steep portions of silt banks in early stages of plant community development in semi-arid grassland ecosystems. The extremely small populations render this moss vulnerable to disturbance. Threats include road development and maintenance, recreational activities, and competition from vascular plants.
COSEWIC History of Status Designation: Designated Endangered in November 2006 and in November 2016.
SARA Status: Schedule 1, Endangered
Date of Listing (yyyy-mm-dd): 2009-03-05

Please note that this information is provided for general information purposes only. For the most up to date and accurate list of species listed under the Species at Risk Act, please see the Justice Laws Website.

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

Description

Nugget Moss is a small moss, less than 2 mm tall, that grows as erect individuals or in small, scattered patches. The leaves are light green to yellow-green or golden green, about 1 mm long, and usually somewhat concave or prow-shaped above. The leaf midrib is pale brown and often wider near the apex than below. In this species, both male and female structures are present on each plant. Sporophytes, which produce spores, mature in late winter or in spring and are immersed in the leaves. The spores, which germinate and grow into new plants, are held in a rounded capsule with a tiny point at the top. Unlike most mosses, the capsules of Nugget Moss do not have a lid that opens to release the spores. Instead, the capsule wall disintegrates as conditions dry into the summer.

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Distribution and Population

In 2013, T. McIntosh identified a few specimens of Nugget Moss in a sample of dryland mosses collected in 1980. The sample was collected on a south-facing silt bank in a wet area near the Porthill border crossing in the Kootenay River Valley (BC Conservation Data Centre 2014). This occurrence has been identified as Rykerts Lake in the BC CDC species occurrence database (Figure 1). T. McIntosh revisited this occurrence in June 2016 and thinks Nugget Moss has likely been extirpated from this occurrence (see next section for details). No targeted surveys of Nugget Moss beyond the three known occurrences have been conducted, with the exception of the 2011 Kamloops area survey, where T. McIntosh and others searched for Nugget Moss on several silt banks west of the known Kamloops location. Although not targeted surveys, T. McIntosh has extensively surveyed lacustrine silt banks in the southern interior of British Columbia for many years. To date, he has found Nugget Moss only at three locations. The loss of the Rykerts Lake site results in a decrease in EOO, IAO and known current locations but it is unknown when this loss occurred. Only one occurrence has been relocated since the initial surveys in 1980. The Penticton subpopulation has been resurveyed in 2004, 2005, 2006, 2011, 2013, and 2016 (COSEWIC 2006; British Columbia Bryophyte Recovery Team 2009; Environment Canada 2012; T. McIntosh, pers. comm. 2016). The Penticton subpopulation has been found at multiple microsites, usually in small (

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Habitat

In British Columbia, Nugget Moss is restricted to undisturbed, exposed, compact silts and clays on post-glacial lacustrine banks in semi-arid grassland and steppe environments where vegetation is sparse. Nugget Moss grows on the partially shaded or highly exposed steep slopes of these banks, where few other moss species are able to grow.

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Biology

Nugget Moss is inconspicuous and grows as individuals or in small, scattered patches on compact, clay-rich soil. Although production of sporophytes is common in Canadian populations, only immature capsules have been observed to date. It is likely that this species needs a relatively prolonged wet spring to enable the spores to mature. Spores, if produced, are probably of importance in the short-range dispersal of this species. Nugget Moss may be a perennial species, since tuber-like structures (absorbent root-like filaments) have been observed on the rhizoids. These “tubers” rich in reserve foods may also be of importance in the survival of the species.

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Threats

The activities/processes identified in the recovery strategies, road/utility construction and maintenance, recreational activities, invasive vascular plants, and unusual storm events, all remain potential threats to Nugget Moss (British Columbia Bryophyte Recovery Team 2009; Environment Canada 2012). In addition, since 2013 three additional threats to the Penticton subpopulation have been identified: new residential development, driving/parking cars on road shoulders, and soil removal (Table 2, K. Sadler, pers. comm. 2016). The most substantial threat to Nugget Moss at both the Penticton and Kamloops occurrence are activities associated with road and utility maintenance and construction (Table 2). Both the Kamloops and Penticton sites are adjacent to roadways. New road construction and maintenance of the existing roads, such as clearing ditches or replacing utilities, could destroy Nugget Moss habitat if not carefully implemented. Environment and Climate Change Canada personnel have revisited the Penticton location in 2013, 2014, 2015, and 2016 to evaluate threats at the site. They noted cars being parked on the shoulder of the road, which could directly destroy Nugget Moss habitat. They also noted a small area where soil had been removed near a previous Nugget Moss observation. The threat of alien invasive vascular plants appears to be more pronounced at the Penticton location. Annual vascular species, such as Prickly Russian Thistle (Salsola tragus) and Yellow Sweet-clover (Melilotus officinalis), were dominant in 2014 in some areas of Nugget Moss habitat (T. McIntosh, pers. comm. 2016). These species could alter Nugget Moss habitat through shading and could also potentially bury Nugget Moss through litter accumulation. Recreational activities, such as hiking, dog walking, and mountain biking, could also destroy Nugget Moss habitat, especially along the lower slopes of silt banks. Some of the silt banks identified as potential critical habitat at the Kamloops location have been designated as a city nature park (Figure 2, Environment Canada 2012). This could lead to greater recreational use of these areas, although existing designated trails avoid Nugget Moss habitat (Stanley 2009). In 2013 a residential development was proposed that could have potentially affected a portion of the Penticton subpopulation. Final subdivision plans are not yet publicly available, but it is possible that the final layout will avoid critical habitat (L. Reiss, pers. comm. 2016). At the Rykerts Lake occurrence, erosion control concerns have led to the area being hydroseeded. Very few mosses appear to have survived this treatment, and it may have led to the extirpation of Nugget Moss at this subpopulation. [Updated 2018-02-19]

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Protection

Federal Protection

The Nugget Moss 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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Recovery Initiatives

Status of Recovery Planning

Recovery Strategies :

Name Recovery Strategy for the Nugget Moss (Microbryum vlassovii) in Canada
Status Final posting on SAR registry

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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.

11 record(s) found.

COSEWIC Status Reports

  • COSEWIC Assessment and Status Report on the Nugget Moss (Microbryum vlassovii) in Canada (2007-08-30)

    The Nugget Moss, Microbryum vlassovii, is one of four species previously included in Phascum in North America. It was known earlier as Phascum vlassovii. It is characterized by the strongly ornamented, sometimes bottle-shaped cells that are present on the upper surface of the leaf lamina and mid-rib, as well as hidden capsules that do not have a lid for spore release.
  • COSEWIC Status Appraisal Summary on the Nugget Moss Microbryum vlassovii in Canada (2017-10-24)

    In Canada, this globally rare moss is known from only three localized sites in semi-arid areas of south-central British Columbia. One of the sites is extirpated and another has not been seen since 1980. The moss grows on fine soils on the steep portions of silt banks in early stages of plant community development in semi-arid grassland ecosystems. The extremely small populations render this moss vulnerable to disturbance. Threats include road development and maintenance, recreational activities, and competition from vascular plants.

Response Statements

  • Response Statement - Nugget Moss (2007-12-04)

    In North America, this globally rare moss is known from only three localized sites. Two of these sites are in semi-arid areas of south-central British Columbia. Recent surveys have re-located the species at only one of these. This moss grows on fine soils on the steep portions of silt banks in early stages of plant community development. The extremely small populations render this moss vulnerable to disturbance. Threats include potential road development and maintenance of existing roads, and collection of specimens.
  • Response Statement - Nugget Moss (2018-01-18)

    In Canada, this globally rare moss is known from only three localized sites in semi-arid areas of south-central British Columbia. One of the sites is extirpated and another has not been seen since 1980. The moss grows on fine soils on the steep portions of silt banks in early stages of plant community development in semi-arid grassland ecosystems. The extremely small populations render this moss vulnerable to disturbance. Threats include road development and maintenance, recreational activities, and competition from vascular plants.

Recovery Strategies

  • Recovery Strategy for the Nugget Moss (Microbryum vlassovii) in Canada (2012-09-21)

    The Nugget Moss was listed on Schedule 1 of the Species at Risk Act (SARA) as Endangered in March 2009. In the spirit of cooperation of the Accord for the Protection of Species at Risk, the Government of British Columbia has given permission to the Government of Canada to adopt the “Recovery strategy for the nugget moss (Microbryum vlassovii) in British Columbia” under Section 44 of the Species at Risk Act. As the competent minister under SARA, the federal Minister of the Environment has included an addition (Part 1) which completes the SARA requirements for this recovery strategy, and excludes the section on Socio-Economic Considerations. Socio-economic factors are not part of the consideration process for federal recovery strategies developed under SARA. These factors are kept isolated from this strategic phase of recovery planning. The British Columbia Ministry of Environment led the development of the attached recovery strategy for the species (Part 2) in cooperation with Environment Canada.

Orders

COSEWIC Annual Reports

  • COSEWIC Annual Report - 2007 (2007-08-30)

    2007 Annual Report to the The Minister of the Environment and the Canadian Endangered Species Conservation Council (CESCC) from the Committee on the Status of Endangered Wildlife in Canada.
  • COSEWIC Annual Report 2016 to 2017 (2017-10-24)

    Over the past year COSEWIC re-examined the status of 40 wildlife species; of these, the majority (78 %) were reassessed at the same or lower level of risk. Of a total of 73 species assessed 11 were assigned the status of Not at Risk (8 re-assessments and 3 new assessments). To date and with the submission of this report, COSEWIC’s assessments now include 735 wildlife species in various risk categories including 321 Endangered, 172 Threatened, 219 Special Concern and 23 Extirpated (i.e. - no longer found in the wild in Canada). In addition 16 species have been assessed as Extinct, 58 have been designated as Data Deficient and 186 were assessed and assigned Not at Risk status.

Consultation Documents

  • Consultation on Amending the List of Species under the Species at Risk Act - Terrestrial Species (2008-03-10)

    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 25, 2008 for species undergoing normal consultations and by March 27, 2009 for species undergoing extended consultations.
  • Consultation on Amending the List of Species under the Species at Risk Act: Terrestrial Species January 2018 (2018-01-26)

    The Government of Canada is committed to preventing the disappearance of wildlife species at risk from our lands. As part of its strategy for realizing that commitment, on June 5, 2003, the Government of Canada proclaimed the Species at Risk Act (SARA). Attached to the Act is Schedule 1, the list of the species provided for under SARA, also called the List of Wildlife Species at Risk. Extirpated, Endangered and Threatened species on Schedule 1 benefit from the protection afforded by the prohibitions and from recovery planning requirements under SARA. Special Concern species benefit from its management planning requirements. Schedule 1 has grown from the original 233 to 555 wildlife species at risk. In 2017, final listing decisions were made for 44 terrestrial species and 15 aquatic species. Of these 59 species, 35 were new additions, sixteen were reclassifications, three had a change made to how they are defined, two were removed from Schedule 1, one was referred back to COSEWIC for further evaluation and two were the object of ‘do not list’ decisions. In 2017, on the recommendation of the Minister of the Environment, the Governor in Council approved listing proposals for 45 wildlife species. It is proposed that 21 species be added to Schedule 1, 11 be reclassified, 12 would have a change made to how they are defined, and one would be referred back to COSEWIC for further evaluation. The listing proposals were published in Canada Gazette, part I for a 30-day public comment period and final listing decisions for all 45 species are expected by August of 2018. Please submit your comments by May 22, 2018, for terrestrial species undergoing normal consultations and by October 22, 2018, for terrestrial species undergoing extended consultations. For a description of the consultation paths these species will undergo, please visit the Species at Risk Public Registry (SAR) website.
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