Hairy Braya

Braya pilosa

General Status Rank: 
At Risk
ELCODE: 
PDBRA0D080
Common Name: 
Hairy Braya
Scientific Name: 
Braya pilosa
Synonyms: 
Hairy Rockcress
Pilose Braya
Naming References: 
W018
Google image search
Taxonomy
Group: 
Vascular Plant
Kingdom: 
Plantae
Phylum: 
Magnoliophyta
Class: 
Dicotyledoneae
Order: 
Brassicales (Capparales)
Family: 
Brassicaceae
References: 
B036
General Biology

Female Age at Maturity

Matures in a single season.

Longevity

Perennial (>10 years).
Habitat
Hairy braya is restricted to an area that remained ice-free during the Pleistocene. The species occurs on bluffs and dry uplands composed of calcareous sandy loam and silty loam soils. It apparently requires bare soil for seedling establishment. Periods of standing water, erosion, and soil disturbance from grizzly bear digs and from caribou and muskox hooves appear to be involved in creating and maintaining these bare soil habitats. Although these habitats are quite extensive on the Cape Bathurst Peninsula, they are often separated from each other by large areas of wet tundra, or by erosion or salinization. Most known individuals are found inland or along protected coastal areas, in habitats that appear to be stable.
References: 
B036
R222
Distribution

Ecozones

Southern Arctic
References: 
B036

Distribution

457 km2. Hairy braya is known to occur only in the NWT, Canada.
Score: 
C
References: 
B036
R222

Number of Occurrences

10 locations, perhaps more on Cape Bathurst Peninsula. There are approximately 19 occurrences (17 extant and 2 extirpated) in four subpopulations located on the northern portion of Cape Bathurst Peninsula and on the nearby Baillie Islands.
Score: 
B
References: 
B036
H152
H160
ASC3
R222

Historical Distribution

References: 
H160

Area of Occupancy

96 km2.
Score: 
D
References: 
R222
Population

Population Size

It is estimated that there are 25,000-50,000 plants in the 17 extant known occurrence sites (distributed among 4 subpopulations). This estimate is based on general estimates made in the field. However, this is likely an underestimate. Population estimates based on density-area calculations from satellite-imagery, which are likely an overestimate, approach 1 million plants. The population is considered self-sustaining.
Score: 
F
References: 
R222
Trends

Trends

Subpopulations on coastal bluffs are subject to rapid erosion and are clearly at risk of declining. Trends in subpopulations on protected sections of the coast and on inland bluffs have not been determined, but the habitats themselves appear to be stable. Two occurrences have been lost to date. The change in population numbers cannot be quantified, but the loss of some coastal sites due to erosion and sea spray has undoubtedly reduced the total number.
Score: 
G
References: 
R222
Threats

Threats

Coastal areas of Cape Bathurst Peninsula and the Baillie Islands are rapidly eroding, and a decrease in Arctic sea ice as well as other climate change-related factors are hastening the erosion of hairy braya habitat along the coast.
Score: 
B

Intrinsic Vulnerability

The species is endemic to the NWT and occurs only in a glacial refugium; there is no possibility of rescue. Hairy braya has specialized habitat requirements and is unlikely to expand its range. It also does not compete well with other plant species when establishing or colonizing new areas.
Score: 
B
General Status Rank
Rank: 
At Risk
Status Rank Description: 
Only known from Cape Bathurst in North America. New survey done in 2011 discovery addition locations (5) and estimated threats to be moderate to severe
S Rank: 
S2
Decision Process Description: 
Drafted as May be at Risk by E. Haber in 2004 (H152). Reviewed in 2010, no change. Modified to at risk due to assessment as Threatened in the NWT (SARC 2012). Reviewed in 2015 by Marilyn Anions; no change.
Last Updated: 
May 4, 2024
Status Designations

NWT - Assessment by Species at Risk Committee

NWT SARC Assessment: 
Threatened
Assessed in 2012. Re-assessed as Threatened in 2024. The extent of occurrence is <20,000 km2 (approximately 457 km2). Area of occupancy is <2,000 km2 (96 km2). Number of locations is 10 with coastal erosion as the most plausible threat, although there may be more locations on the Cape Bathurst Peninsula. Increased range and numbers since the last assessment are due to an expanded search effort and research on its range. This species does not exist anywhere else in the world and is found in a very small area of the NWT that remained unglaciated during the last glacial period. Coastal habitat continues to decline (~10m/year erosion) and this is expected to increase due to climate change. Increasing sea level, storm surges, longer ice-free periods and melting permafrost all contribute to accelerating coastal erosion. Hairy braya only exists on Cape Bathurst Peninsula and Baillie Islands in the NWT, so there is no possibility of rescue from outside populations. The species has specialized habitat requirements and is unlikely to expand its range. Hairy braya does not compete well with other plant species when establishing or colonizing new areas. Salinization is affecting coastal habitat, resulting in population decline. Increased drought conditions and lightning-caused wildfires are potential threats to the species.
References: 
R222

NWT - Species at Risk Legal Status

NWT Status Rank: 
Threatened
Threatened - 2014. An NWT recovery strategy was completed in 2016 and a progress report was released in 2021.

Canada – Assessment by Committee on the Status of Endangered Wildlife in Canada

COSEWIC Status: 
Endangered
2013.
References: 
R232

Canada – Species at Risk Legal Status

SARA Status: 
Endangered
2018.
References: 
W103

References

Area of Occupancy

  • SARC (2012) Species status report on Hairy Braya in the NWT.. Species status report on Hairy Braya in the NWT. - R222 Return
COSEWIC Status
  • COSEWIC (2013) COSEWIC status report on Hairy Braya in Canada. Environment Canada - R232 Return

Ecozones

  • McJannet CL, Argus GW and Cody WJ (1995) Rare Vascular Plants in the Northwest Territories. Canadian Museum of Nature Syllogeus 73:1-104. RWED Library Call #QK86.C3M3 - B036 Return

Federal Species at Risk Status

  • Government of Canada (2016) Species at Risk Public Registry. http://www.sararegistry.gc.ca/default_e.cfm - W103 Return

Habitat

  • McJannet CL, Argus GW and Cody WJ (1995) Rare Vascular Plants in the Northwest Territories. Canadian Museum of Nature Syllogeus 73:1-104. RWED Library Call #QK86.C3M3 - B036 Return
  • SARC (2012) Species status report on Hairy Braya in the NWT.. Species status report on Hairy Braya in the NWT. - R222 Return

Historical Distribution

  • Jim Harris (2004) Braya pilosa. From: Jim Harris [HARRISJI@uvsc.edu] Sent: Tuesday, October 05, 2004 12:17 PM To: Bruce.Bennett@gov.yk.ca Subject: RE: Braya pilosa Copy of e-mail in Reference binder - H160 Return

Naming

  • NatureServe: An online encyclopedia of life [web application]. (2001) Version 1.4 . Arlington, Virginia, USA: Association for Biodiversity Information.. Available: http://www.natureserve.org/. (Accessed: June 29, 2001 - W018 Return

Number of Occurrences

  • McJannet CL, Argus GW and Cody WJ (1995) Rare Vascular Plants in the Northwest Territories. Canadian Museum of Nature Syllogeus 73:1-104. RWED Library Call #QK86.C3M3 - B036 Return
  • Erich Haber (2004) Personal Communication- email to S. Carriere on 9/16/2004 with dicot 2.. email archive (printed version in GSR binders) - H152 Return
  • Jim Harris (2004) Braya pilosa. From: Jim Harris [HARRISJI@uvsc.edu] Sent: Tuesday, October 05, 2004 12:17 PM To: Bruce.Bennett@gov.yk.ca Subject: RE: Braya pilosa Copy of e-mail in Reference binder - H160 Return
  • Harris, J. G. (2004) Braya pilosa HOOKER (Cruciferae), an enigmatic endemic of arctic Canada.. Unpublished manuscript sent by e-mail 25Oct. 2004 Published in CFN 2004 118(4): 550-557 Papercopy in reference binder - ASC3 Return
  • SARC (2012) Species status report on Hairy Braya in the NWT.. Species status report on Hairy Braya in the NWT. - R222 Return

NWT SARC Assessment

  • SARC (2012) Species status report on Hairy Braya in the NWT.. Species status report on Hairy Braya in the NWT. - R222 Return

Population Size

SARC (2012) Species status report on Hairy Braya in the NWT.. Species status report on Hairy Braya in the NWT. - R222 Return

Range Extent

  • McJannet CL, Argus GW and Cody WJ (1995) Rare Vascular Plants in the Northwest Territories. Canadian Museum of Nature Syllogeus 73:1-104. RWED Library Call #QK86.C3M3 - B036 Return
  • SARC (2012) Species status report on Hairy Braya in the NWT.. Species status report on Hairy Braya in the NWT. - R222 Return

Short Term Trends

  • SARC (2012) Species status report on Hairy Braya in the NWT.. Species status report on Hairy Braya in the NWT. - R222 Return

Taxonomy

  • McJannet CL, Argus GW and Cody WJ (1995) Rare Vascular Plants in the Northwest Territories. Canadian Museum of Nature Syllogeus 73:1-104. RWED Library Call #QK86.C3M3 - B036 Return