Species Profile

California Buttercup

Scientific Name: Ranunculus californicus
Taxonomy Group: Vascular Plants
COSEWIC Range: British Columbia
COSEWIC Assessment Date and Status Change: November 2008
COSEWIC Status: Endangered
COSEWIC Status Criteria: B1ab(iii)+2ab(iii)
COSEWIC Reason for Designation:

A perennial species restricted to two small island groups adjacent to Victoria, BC. The four small confirmed populations are found within coastal meadow habitats where the extensive spread of invasive plants place the species at risk. Potential impacts on the populations include planned enlargement of communications towers at one site and unauthorized recreational visitors to the island habitats.
COSEWIC History of Status Designation: Designated Endangered in November 2008.
SARA Status: Schedule 1, Endangered
Date of Listing (yyyy-mm-dd): 2011-02-04

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 | Recovery Team | National Recovery Program | Documents


California Buttercup is a low, hairy perennial. The numerous stems are sprawling to erect and 15 to 50 cm long. The stems each generally have several shiny, lemon-yellow flowers in an open inflorescence. The flowers have up to 16 petals, unlike most species of buttercup, which typically have only 5 petals. During the spring, the species produces lobed basal leaves that are 2 to 8 cm long. This species is easily recognized by its showy, multi-petalled flowers. It is also readily distinguished from similar buttercup species, such as the Western Buttercup with which it hybridizes in British Columbia, by the curved beak on the dry fruits, or achenes.


Distribution and Population

California Buttercup is found along the west coast of North America, from southwestern British Columbia and the adjacent part of the state of Washington to Baja California where it is widespread. In British Columbia, it is restricted to two small island clusters that lie southeast of Victoria. Records from 2003 and 2005 indicate that there are four small confirmed California Buttercup populations in British Columbia and perhaps a fifth reported population on private land that could not be confirmed. There are believed to be between 3100 and 3600 individuals in these known populations. Searches throughout the British Columbian extent of potential occurrence have not resulted in any new populations of the species, although some sites adjacent to known populations appear to support hybrids. Given the lack of reliable long-term information on past population sizes of this species in Canada, current population trends are unknown. However, the amount of potential habitat has declined over the last century as a result of the partial development of coastal meadows for residential and recreational use. Because of limitations in seed dispersal, colonization and development of new populations is unlikely.



In Canada, California Buttercup is restricted to open coastal meadows on oceanic bluffs exposed to wind and salt spray on the southeast coast of Vancouver Island, which is characterized by mild, wet winters and cool, dry summers. It occurs in sites that remain open because of wind exposure along the shore, summer drought in thin soils, and winter seepage that waterlogs soils, preventing taller vegetation from dominating. California Buttercup is restricted to areas within 50 m of the coast, where frequent coastal fogs occur in the fall and winter and the climate is buffered against deep frosts in the winter.



Very little is known about the biology of this species. However, it is known that California Buttercup is normally a perennial species but sometimes acts as an annual in Canada. It is primarily bee-pollinated, although pollination may also be accomplished by thrips and flies. No specific information is known about seed dispersal in this species, but it is thought to be by adhesion to fur, feathers or clothing. Wind is also thought to contribute to seed dispersal for short distances. If California Buttercup is eaten by voles, as is the case with other buttercup species, its seeds could also germinate after passage through animal digestive systems and thus would be dispersed by the animal’s movement. However, since the species does not seem to be grazed by any herbivores in the islands and islets to which it is restricted, this mode of dispersal seems unlikely. Finally, California Buttercup is adapted to conserve moisture during the dry summer months.



Limitations for the California Buttercup populations in Canada are habitat loss through development, and alteration of habitat, particularly resulting from the invasion of sites by alien species. Extant populations of California Buttercup have generally been observed growing in a matrix dominated by many invasive alien species, which threaten them in various ways. First, shrubs and tall grasses shade out California Buttercup. Second, many grasses and forb species may outcompete California Buttercup for moisture and nutrients. Third, alien annual species prevent California Buttercup from colonizing suitable sites through their ability to pre-empt such sites. Perennial aliens may have established permanent cover in sites that formerly provided a constant supply of bare mineral soil. Another major threat to the species is recreational activities. A portion of one population occurs in the campground of a provincial marine park and has been mowed repeatedly. The balance of that population occurs in the immediate vicinity of a walking trail through the marine park. Although the other populations are located within reserves where recreational activities are prohibited, they are located in spots that are used nevertheless for recreation, particularly by picnickers who arrive by boat from Victoria. One of the populations occurs on an Indian reserve and could be placed at risk by the planned enlargement of communications towers. One other factor contributing to the decline of California Buttercup is fire suppression. Pre-European fire regimes in the dry coastal belt of southeast Vancouver Island killed young Red Alder and Douglas-fir and checked the growth of Trembling Aspen and most shrub species. The increase in light levels and decrease in competition resulting from fires favour low plants such as California Buttercup. In the absence of burning, the availability of suitable habitats has likely diminished.



Federal Protection

The California Buttercup 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.

California Buttercup is not protected by any provincial legislation in British Columbia.

Provincial and Territorial Protection

To know if this species is protected by provincial or territorial laws, consult the provinces' and territories' websites.


Recovery Initiatives

Status of Recovery Planning

Recovery Strategies :

Name Recovery Strategy for the California Buttercup (Ranunculus californicus) in Canada
Status First posting on SAR registry


Recovery Team

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.

7 record(s) found.

COSEWIC Status Reports

  • COSEWIC Assessment and Status Report on the California Buttercup Ranunculus californicus in Canada (2009-08-28)

    California Buttercup Ranunculus californicus is a low-growing, erect to flattened on the ground perennial species of buttercup with shiny lemon-yellow petals. It is readily distinguished from other buttercup species by its multiple petals (up to 16). Other similar species of buttercup, such as the western buttercup, typically have only 5 petals. California Buttercup readily hybridizes with the Western Buttercup, but can be easily distinguished by the curved beak on the fruitlets.

Response Statements

  • Response Statement - California Buttercup (2009-11-25)

    A perennial species restricted to two small island groups adjacent to Victoria, BC. The four small confirmed populations are found within coastal meadow habitats where the extensive spread of invasive plants place the species at risk. Potential impacts on the populations include planned enlargement of communications towers at one site and unauthorized recreational visitors to the island habitats.

Recovery Strategies

  • Recovery Strategy for the California Buttercup (Ranunculus californicus) in Canada (2013-11-06)

    The Canadian population of the California Buttercup (Ranunculus californicus Benth.) was assessed as Endangered in 2008 by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), and in February 2011 the population was listed as Endangered under Canada’s Species at Risk Act (SARA) Schedule 1. The California Buttercup is a low growing perennial herb with lemon-yellow, flowers (with up to 16 petals), and hairy stems ranging from 15–50 cm tall. It ranges from British Columbia south along the coast to Baja California, but the Canadian population is widely disjunct from the nearest Oregon population. The Canadian population of California Buttercup comprises Due to minor inconsistencies in the French and English versions of this recovery strategy, a slightly modified document in each language has replaced the one originally posted. Due to this error, the 60-day comment period will end June 11, 2013.


COSEWIC Annual Reports

  • COSEWIC Annual Report - 2009 (2009-08-28)

    2009 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.

Consultation Documents

  • Consultation on Amending the List of Species under the Species at Risk Act: Terrestrial Species, December 2009 (2009-12-17)

    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 1, 2010 for species undergoing normal consultations and by March 1, 2011 for species undergoing extended consultations.
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