BC Conservation Data Centre: Conservation Status Report
Abronia umbellata var. breviflora
pink sand-verbena
| Scientific Name: | Abronia umbellata var. breviflora |
|---|---|
| Scientific Name Synonyms: |
Abronia umbellata ssp. acutalata
Abronia umbellata ssp. breviflora |
| English Name: | pink sand-verbena |
| Provincial Status Summary | |
| Status: | S1 |
| Date Status Assigned: | May 20, 2004 |
| Date Last Reviewed: | April 30, 2019 |
| Reasons: | Abronia umbellata var. breviflora has been found at only three sites in B.C. No living populations have been seen in the province since 2001. There are currently no populations in the province with good viability. Populations have probably declined by 10% over the last 10 years and about 30% since the last century because of habitat loss caused by the spread of Ammophila. More than 60% of occurrences are likely threatened by habitat loss. Abronia umbellata var. breviflora is highly vulnerable because of irregular dispersal and highly fragmented populations, inhospitable habitat, and potential recreational impacts. It has very narrow environmental specificity. |
| Range | |
| Range Extent: | Z = Zero (no occurrences believed extant) |
| Range Extent Comments: | In British Columbia, Abronia umbellata var. breviflora occurs at the most northern edge of its range. Historically, it has been found at three sites on the outer coast of Vancouver Island. The number of occurrences and individuals fluctuates greatly, and populations appear to be short-lived because of harsh habitat conditions. Populations were seen most recently in 2000 and 2001 but have not been seen since. The subspecies is currently considered extirpated in the province, but it could potentially reappear and disappear on an irregular basis. The closest known existing populations are on the coast of Oregon. |
| Area of Occupancy (km2): | Z = Zero (no occurrences believed extant) |
| Linear Distance of Occupancy: | Z = Zero (no occurrences believed extant) |
| Area of Occupancy Comments: | No populations are currently known to exist in British Columbia. |
| Occurrences & Population | |
| Number of Occurrences: | Z = 0 (zero) |
| Comments: | No living populations observed in British Columbia since 2001. |
| Number of Occurrences with Good Viability / Ecological Integrity: | A = No (A- or B-ranked) occurrences with good viability |
| Comments: | There are currently no populations with good viability in the province. |
| Number of Occurrences Appropriately Protected & Managed: | A = None. No occurrences appropriately protected and managed |
| Comments: | No living populations have been seen in the province since 2001. The most recently observed population occurred within Pacific Rim National Park, where protective measures included flagging, but this population was washed away in the winter storms of 2001/2002. |
| Population Size: | Z = Zero, no individuals extant |
| Comments: | No living populations have been seen in the province since 2001. |
| Threats (to population, occurrences, or area affected) | |
| Degree of Threat: | A = Substantial, imminent threat |
| Comments: | More than 60% of occurrences are likely threatened. The threat is moderate with ongoing long-term loss or degradation of habitat. The greatest threat is the spread of the exotic dune grasses, Ammophila arenaria (European beachgrass) and Ammophila breviligulata (sand-reed), which arrest sand movement and eventually stabilize upper beach and foredune systems. This excludes native vegetation and destroys habitat for Abronia. At Wickaninnish Beach (Pacific Rim National Park), one of the most extensive beaches on the outer coast of British Columbia, Ammophila has greatly reduced potential habitat for Abronia umbellata var. breviflora. The vigorously growing rhizomatous Ammophila grasses have created heavily vegetated foredunes. These grasses also intrude on the upper sand beaches. Ammophila is difficult to eradicate because of its extensive underground network of rhizomes and poor response to herbicides. It is now so widespread on the west coast of the United States that its eradication, except in local situations, is presently impossible. A second but natural threat to Abronia umbellata var. breviflora is the harsh habitat it inhabits, which is scoured by high tides and winter storms; few plants ever persist over winter. A third potential threat to A. umbellata var. breviflora is recreational activity. There are often numerous hikers in areas of potential Abronia habitat on beaches of the outer coast. Trampling may damage populations, and the plant's attractive pink flowers may cause some losses to casual collecting or digging for garden purposes. |
| Trend (in population, range, area occupied, and/or condition of occurrences) | |
| Short-Term Trend: | E = Stable (unchanged or within +/- 10% fluctuation in population, range, area occupied, and/or number or condition of occurrences |
| Comments: | Populations have probably declined about 10% over the last 10 years because of habitat loss caused by the spread of exotic Ammophila arenaria (European beachgrass) and Ammophila breviligulata (sand-reed). Ammophila presumably has considerably reduced the amount of suitable habitat for Abronia in the province. |
| Long-Term Trend: | D = Moderate decline (decline of 25 - 50%) |
| Comments: | Populations in B.C. have probably declined about 30% over the last century because of habitat changes caused by the spread of exotic dune grasses. Occurrences of Abronia are ephemeral, the habitat is harsh, and the species appears to never have been common. It has been documented only five times (1915, 1927, 1941, 2000, 2001) from only three sites (COSEWIC 2004h). |
| Other Factors | |
| Intrinsic Vulnerability: | A = Highly vulnerable |
| Comments: | Abronia umbellata var. breviflora is highly vulnerable because of irregular dispersal and highly fragmented populations. |
| Environmental Specificity: | A = Very narrow. Specialist or community with key requirements scarce. |
| Comments: | Abronia umbellata var. breviflora has very narrow environmental specificity. Its habitat in British Columbia is restricted to upper sand beaches, just below the driftwood zone, along the outer west coast of Vancouver Island. These sites are scoured by high tides and winter storms; thus, few plants ever persist over winter. |
| Other Rank Considerations: | Long-term survival may be possible because the extreme toughness of the fruits may enable them to persist for years in the seed bank and germinate successfully after long-distance dispersal on ocean currents. It is likely that the seed bank of the ephemeral beach habitat rarely results in large numbers of plants germinating in any given year. Despite the potential for low genetic variability because isolated populations have little chance of outcrossing, experimental work indicates that genetic variation remains high. Abronia umbellata var. breviflora is ephemeral, habitat conditions change from year to year, and populations reappear and disappear on an irregular basis. |
| Information Gaps | |
| Research Needs: | The current extent of both species of Ammophila should be delineated with GIS and the rate of spread determined by comparison with historical air photography for the outer coast of Vancouver Island, if available. This will help quantify habitat loss for Abronia umbellata var. breviflora and future threats to it. |
| Inventory Needs: | Abronia umbellata var. breviflora can be detected only by making annual surveys of beaches each spring and summer, preferably during the flowering period. Any sites with Abronia latifolia are also potential habitat for A. umbellata var. breviflora, so all suitable beaches should be searched. Slightly more stabilized dunes behind the foredune should also be searched. |
| Stewardship | |
| Protection: | Given the ephemeral habit of this subspecies and its harsh habitat conditions, not much can be done to protect or enhance populations other than protecting known stands from recreational impacts and controlling the spread of Ammophila. |
| Management: | Eradication of Ammophila is a difficult and challenging problem for land managers. To date, chemical, manual, and mechanical control have had only moderate success. With much effort, local areas can be successfully cleared of Ammophila and sand movement restored, but the future challenge will be to apply these techniques or find new ones that are more successful on a much larger landscape scale. Some populations may require protection from hikers or casual collectors. Abronia has been reintroduced experimentally to former habitat in Oregon, and such work could be done in B.C. to re-establish populations. Transplants and seedings had moderate success at some sites and low success at others, but they demonstrate that it is possible to re-establish populations of Abronia, at least for the short term. |
| Version | |
| Author: | Christy, J.A. |
| Date: | January 31, 2005 |
| References | |
|
Backhouse, F. 2000. Extinct and Extirpated Species. B.C. Minist. Environ., Lands and Parks, Wildl. Branch. 6pp.
|
|
|
COSEWIC. 2004h. COSEWIC assessment and status report on the pink sand-verbena Abronia umbellata in Canada. Comm. on the Status of Endangered Wildl. in Can. Ottawa. vii + 19 pp.
|
|
|
Douglas, G.W. 2003b. Status Report on Pink Sand-verbena Abronia umbellata ssp. breviflora in Canada. Unpubl. Rep. submitted to the Comm. on the Status of Endangered Wildl. in Canada. Ottawa. 22pp.
|
|
|
Douglas, G.W., D. Meidinger, and J. Penny. 2002. Rare Native Vascular Plants of British Columbia, 2nd ed. B.C. Conserv. Data Centre, Terrestrial Inf. Branch, Victoria. 358pp.
|
|
|
Fairbarns, M. 2011. Pink Sand-verbena (Abronia umbellata) 2010-1. Summary and Synthesis of Recovery Acitivities. Prepared for Parks Canada Agency. Vancouver, BC. 24 pp.
|
|
Please visit the website Conservation Status Ranks for information on how the CDC determines conservation status ranks. For global conservation status reports and ranks, please visit the NatureServe website http://www.natureserve.org/.
Suggested Citation:
B.C. Conservation Data Centre. 2005. Conservation Status Report: Abronia umbellata var. breviflora. B.C. Minist. of Environment. Available: https://a100.gov.bc.ca/pub/eswp/ (accessed Jun 25, 2026).