Baker's Larkspur

Delphinium bakeri

Description

Baker's larkspur (Delphinium bakeri ) is a perennial herb that grows from a thickened, tuber-like cluster of roots. Its stems are hollow, erect, and grow as tall as 26 in (65 cm). Its leaves are shallowly five-parted, and occur mostly on the upper third of the stem. The flowers are irregularly shaped, with five conspicuous sepals comprising the outermost whorl of floral parts. The sepals are colored a bright dark-blue or purplish, and the rear sepal is elongated into a spur. The petals are inconspicuous and occur in two pairs. The lower pair is oblong and blue-purple, while the upper pair is oblique and white. Seeds are produced in dry, many-seeded fruits, which open at maturity by splitting on one side.

Baker's larkspur flowers from April through May. It is pollinated by insects. Its seeds are locally distributed from the ripe capsules. Reproduction is by seedling establishment.

Habitat

Baker's larkspur occurs within the coastal scrub plant community, an open, shrubby habitat occurring at the top of seacliffs. It grows in soil derived from decomposed shale, at elevations of 400-500 ft (120-150 m).

Distribution

Baker's larkspur is a locally evolved (or endemic) species that is only known from Coleman Valley in Sonoma County, and from a site near Tomales in Marin County, both in California.

Threats

Baker's larkspur has declined in abundance and local range because of the conversion of its natural habitat into agricultural land use. It has also suffered from direct damage and habitat degradation caused by grazing livestock and roadside maintenance activities. The only known surviving population of Baker's larkspur, with about 35 plants, occurs on a steep road bank on private and county land in Marin County. This site is threatened by road maintenance, the collection of plants by botanists and horticulturists, and sheep grazing. Because of its small population size and very local range, Baker's larkspur is also threatened by unpredictable disturbances, such as wildfire, insect outbreaks, or extreme weather.

Conservation and Recovery

The collection or disturbance of wild Baker's larkspur is now illegal, although this is difficult to enforce and the surviving plants and their seed capsules are vulnerable to harvesting for use in gardens or the commercial horticultural trade. In addition, under state law private landowners can in some circumstances remove plants after providing the California Department of Fish and Game ten days advance notice. The sole surviving population remains potentially vulnerable to damage from road maintenance activities, although local authorities are aware of the location of the critical habitat of this endangered plant are try to avoid it when planning their work activities. The U. S. Fish and Wildlife Service intends to propose a designation of critical habitat for Baker's larkspur in the future, probably during 2002. Thus should include the designation of the habitat as a protected area, either through acquisition of the private land or by negotiation of a conservation easement.

Contacts

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Complex
911 N. E. 11th Ave.
Portland, Oregon 97232-4181
Telephone: (503) 231-6121
http://pacific.fws.gov/

U. S. Fish and Wildlife Service, Sacramento Fish
and Wildlife Office
Cottage Way, Room W2605
Sacramento, California 95825
Telephone: (916) 414-6464
Fax: (916) 414-6486)

Reference

U. S. Fish and Wildlife Service. 26 January 2000. "Endangered and Threatened Wildlife and Plants; Determination of Endangered Status for Two Larkspurs From Coastal Northern California." Federal Register 65 (17): 4156-4162.