Scientific Name: Triteleia howellii
Taxonomy Group: Vascular Plants
COSEWIC Range: British Columbia
COSEWIC Assessment Date and Status Change: May 2003
COSEWIC Status: Endangered
COSEWIC Status Criteria: B1ab(ii,iii,iv,v)+2ab(ii,iii,iv,v)
COSEWIC Reason for Designation: This is a geographically highly restricted species with a small population occurring at a few scattered sites within remnant Garry oak habitats. It is located within a highly urbanized region with on-going risks to the species from such factors as habitat loss, competition with invasive species, habitat loss, habitat fragmentation and competition with invasive species.
COSEWIC History of Status Designation: Designated Endangered in May 2003.
SARA Status: Schedule 1, Endangered
Date of Listing (yyyy-mm-dd): 2005-01-12
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.
Howell's Triteleia is one of three native species in Canada belonging to the lily family. It is a perennial herb that grows from an underground stem structure, similar to a bulb, called a corm. The flower stalk is 20 to 50 cm tall with one or two smooth and slender leaves, 20 to 40 cm long and 3 to 8 mm wide, at the base. The 3-to-4-cm-long flowers are formed from six whitish to blue, narrowly bell-shaped segments. The segments are fused at the base and spread into two petal-shaped whorls. The fruit is an egg-shaped capsule containing black, rounded seeds.
Distribution and Population
Howell’s Triteleia ranges from southwestern British Columbia to northern California in the United States. It is only known from 12 sites in Canada, all of which are located on southeastern Vancouver Island. Nine of these 12 sites have been confirmed since 1997. The status of the plants at the remaining three sites is unknown and the populations may be extirpated. At the nine existing sites, population areas range from small (1 m²) to over three or four hectares, while plant numbers range from a single plant to over 450.
Howell's Triteleia occurs in the Garry Oak woodland — a unique ecosystem in Canada found within a limited habitat type, the Coastal Douglas-fir zone. This zone encompasses southeastern Vancouver Island, several islands in the Gulf of Georgia and a narrow strip of adjacent mainland in British Columbia. It is in a rainshadow belt created by the Olympic and Vancouver Island mountains — resulting in a Mediterranean climate with warm, dry summers and mild, wet winters. More specifically, Howell's Triteleia grows in Garry Oak Quercus garryana woodlands, and in highly disturbed sites dominated by weeds in private yards and on roadsides.
There is little known about the biology of Howell's Triteleia throughout its range. Reproduction is through division of the corm, by the production of numerous cormlets, and by seed. The bulb-like corms of this species are edible and, like other related species, may have been used by native peoples as a food source.
The most direct and immediate threat to Triteleia howellii is habitat destruction. The Garry Oak communities are limited to the southeastern side of Vancouver Island and some of the Gulf Islands, and have been heavily urbanized. The suppression of fire and the spread of introductions has also been a limiting factor. One of the most devastating introduced species is Scotch Broom Cytisus scoparius; it has become a dominant shrub on dry, exposed sites throughout much of southeastern Vancouver Island and the Gulf Islands. Furthermore, dispersal into new sites is likely limited and some of the populations of Howell's Triteleia contain very few plants.
The Howell's Triteleia 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.
The nine confirmed populations of Howell's Triteleia occur in regional and municipal parks, as well as on private properties.
Provincial and Territorial Protection
Status of Recovery Planning
Recovery Strategies :
Name Recovery Strategy for Multi-species at Risk in Garry Oak Woodlands in Canada
Status Final posting on SAR registry
Garry Oak Ecosystems Recovery Team
Conan Webb - Chair/Contact - Parks Canada
Phone: 250-478-5153 Send Email
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.
8 record(s) found.
- COSEWIC Status Reports (1 record(s) found.)
- Response Statements (1 record(s) found.)
- Recovery Strategies (1 record(s) found.)
- Orders (2 record(s) found.)
- Permits and Related Agreements (2 record(s) found.)
- Consultation Documents (1 record(s) found.)
COSEWIC Status Reports
Response Statements - Howell's Triteleia (2004-04-21)A response statement is a communications document that identifies how the Minister of the Environment intends to respond to the assessment of a wildlife species by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). The document provides a start to the listing and recovery process for those species identified as being at risk, and provides timelines for action to the extent possible.