Fragrant popcornflower (Plagiobothrys figuratus) COSEWIC assessment and status report: chapter 2

COSEWIC Executive Summary

Fragrant popcornflower
Plagiobothrys figuratus

Species information

Fragrant popcornflower (Plagiobothrys figuratus) is a showy annual herb belonging to the Borage family and is native to the Pacific Northwest. It has fragrant white flowers and hairy stems. Plants range in height from 10-45 cm. The Canadian plants are recognized as ssp. figuratus. This is the only subspecies in Canada. A second subspecies, Plagiobothrys figuratus ssp. corallicarpus, is endemic to Oregon.

Distribution

The native range of the species extends from southeastern Vancouver Island (Nanaimo, Victoria, and Gulf Islands) south to Oregon west of the Cascade Mountains, and east to the Columbia River Gorge in Washington. The ssp. corallicarpus occurs only in southwestern Oregon where it overlaps the range of the common ssp. figuratus. Fragrant popcornflower occurs as an introduced species in parts of southern Alaska and the eastern U.S. The historical Extent of Occurrence (EO) in Canada was about 1600 km². Its current confirmed EO, based on a single extant population, is << 1 km². The actual area of habitat once covered by the species is unknown, but the single extant population covers an area of about 1 , with its official Area of Occupancy, based on a 1x1 km grid being 1 km².

Habitat

Fragrant popcornflower prefers low-lying, wet areas and is usually found in moist fields and open meadows, occasionally also along watercourses and ditches. Increasingurbanization around Victoria and Nanaimo, combined with the draining of wetlands for agricultural uses and road construction, has altered the ecology of the region to such an extent that the amount of area suitable for supporting this species is now significantly reduced compared to historical levels.

Biology

Fragrant popcornflower is an annual plant that produces a coiled head of showy flowers in May or June. Each flower produces 2-4 smooth seeds. Little else is known about the ecology of this species, including its survival and recruitment rates, dispersal mechanisms, and intrinsic vulnerabilities to disturbance.

Population sizes and trends

The first Canadian collection of fragrant popcornflower was made in 1885, near Victoria. It is known historically from 7-12 independent localities. The species was recently thought to have been extirpated in Canada, having last been recorded at Hornby Island, British Columbia, in the 1980s. However, in 2005, a single flowering plant was observed at Hornby Island, but no plants were seen in 2006.

Limiting factors and threats

The ecological factors naturally limiting the abundance and distribution of this species are largely unknown. Urbanization is likely the primary reason that this species has largely disappeared from its Canadian range, as the majority of former habitats were located in what are now the cities of Nanaimo and Victoria. The greatest current threats to fragrant popcornflower persistence appear to be residential development, small population size, and competition from invasive alien species.

Special significance of the species

Seeds of this attractive species are offered for horticultural use. The species has also been suggested for inclusion in a mix of herbaceous plants to be used in wetlands to control the spread of reed canary grass (Phalaris arundinacea). It has no known ethnobotanical uses.

Existing protection or other status designations

No protection currently exists for fragrant popcornflower,although it is a potential candidate for listing under the British Columbia Wildlife Amendment Act (2004).

COSEWIC History

The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) was created in 1977 as a result of a recommendation at the Federal-Provincial Wildlife Conference held in 1976. It arose from the need for a single, official, scientifically sound, national listing of wildlife species at risk. In 1978, COSEWIC designated its first species and produced its first list of Canadian species at risk. Species designated at meetings of the full committee are added to the list. On June 5, 2003, the Species at Risk Act (SARA) was proclaimed. SARA establishes COSEWIC as an advisory body ensuring that species will continue to be assessed under a rigorous and independent scientific process.

COSEWIC Mandate

The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) assesses the national status of wild species, subspecies, varieties, or other designatable units that are considered to be at risk in Canada. Designations are made on native species for the following taxonomic groups: mammals, birds, reptiles, amphibians, fishes, arthropods, molluscs, vascular plants, mosses, and lichens.

COSEWIC Membership

COSEWIC comprises members from each provincial and territorial government wildlife agency, four federal entities (Canadian Wildlife Service, Parks Canada Agency, Department of Fisheries and Oceans, and the Federal Biodiversity Information Partnership, chaired by the Canadian Museum of Nature), three non-government science members and the co-chairs of the species specialist subcommittees and the Aboriginal Traditional Knowledge subcommittee. The Committee meets to consider status reports on candidate species.

Definitions (2008)

Wildlife Species
A species, subspecies, variety, or geographically or genetically distinct population of animal, plant or other organism, other than a bacterium or virus, that is wild by nature and is either native to Canada or has extended its range into Canada without human intervention and has been present in Canada for at least 50 years.

Extinct (X)
A wildlife species that no longer exists.

Extirpated (XT)
A wildlife species no longer existing in the wild in Canada, but occurring elsewhere.

Endangered (E)
A wildlife species facing imminent extirpation or extinction.

Threatened (T)
A wildlife species likely to become endangered if limiting factors are not reversed.

Special Concern (SC)Footnotea
A wildlife species that may become a threatened or an endangered species because of a combination of biological characteristics and identified threats.

Not at Risk (NAR)Footnoteb
A wildlife species that has been evaluated and found to be not at risk of extinction given the current circumstances.

Data Deficient (DD)Footnotec
A category that applies when the available information is insufficient (a) to resolve a species’ eligibility for assessment or (b) to permit an assessment of the species’ risk of extinction.

 

Canadian Wildlife Service

The Canadian Wildlife Service, Environment Canada, provides full administrative and financial support to the COSEWIC Secretariat.

 

Page details

Date modified: