Cordylanthus tenuis ssp. capillaris
|Listed||February 3, 1995|
|Description||Branching herbaceous annual with yellow-green hairless herbage that becomes purplish with age.|
|Habitat||Serpentine flats among chaparral at elevations of approximately 150-800 ft (46-244 m).|
|Threats||Potential residential development, timber harvest activities, garbage dumping, slope erosion, off-road vehicle use, maintenance.|
Pennell's bird's-beak, Cordylanthus tenuis ssp. capillaris, is a branching herbaceous annual of the snapdragon family (Scrophulariaceae). The plant grows 12-24 in (30.5-61 cm) tall, with yellow-green hairless herbage that becomes purplish with age. The leaves are entire, or those of the primary stem three-parted, and threadlike. The floral bracts are three-parted up to two-thirds of their length, with fine marginal hairs on bracts and calyx. The tubular corolla is 0.6 in (1.5 cm) long, and garnet-brown laterally, paler dorsally. Each capsule contains 10-16 seeds. The three-lobed outer bracts of C. tenuis ssp. capillaris distinguish it from its nearest relative, C. tenuis ssp. brunneus, and from C. pilosus, another Cordylanthus found in the area. A further distinguishing character is that C. pilosus is densely hairy throughout.
Pennell's bird's-beak flowers from June to July. The species is a root parasite, forming attachments to shrubs and possibly cypress trees.
Pennell's bird's-beak occupies serpentine flats among chaparral at elevations of approximately 150-800 ft (46-244 m). Associated species include Baker's manzanita, California coffeeberry, musk brush, and Sargent cypress. Of these, Baker's manzanita is considered rare.
Pennell's bird's-beak is known only from the vicinity of Camp Meeker in Sonoma County. The species is found in two locations: the type locality which is partially within the Harrison Grade Ecological Reserve in western Sonoma County and a second area a few miles to the west near Bohemian Highway. A third population may occur on property adjacent to the second location, but permission for botanical surveys on that property has been consistently refused.
The Harrison Grade Ecological Reserve location had more than 5,000 plants in 1987. The Bohemian Highway location consists of two populations, one with approximately 200 plants growing on a steep slope in 1987 and the other with 12 plants in a roadside ditch in 1986. The total number of plants fluctuates from year to year, as is typical of annual plants.
Pennell's bird's-beak is threatened by potential residential development, timber harvest activities, garbage dumping, slope erosion, off-road vehicle use, and roadside maintenance. Vehicular traffic threatens plants in and near the parking area at the Harrison Grade Reserve, which is poorly defined and close to the plant population. Unauthorized dumping of items such as bottles, furniture, and appliances, and trampling by visitors are also threats to the species at the site. Light disturbance at the Harrison Grade Reserve, such as infrequent grading of dirt roads, appears to increase the numbers of Pennell's bird's-beak, but higher levels of disturbance may facilitate the invasion of non-native species and result in a decline of Pennell's bird's-beak.
The second location of Pennell's bird's-beak occurs on private property in the vicinity of Bohemian Highway. The owner of the property had been working with the California Department of Fish and Game to minimize impacts to Pennell's bird's-beak, and to donate 212 acres (85.8 hectares), including Pennell's bird's-beak habitat, to the county for use as a park. However, in 1997, planning for the subdivision and associated park was dropped and the property sold to another party who is making plans for timber harvest activities and development.
Both horses and deer have been reported to browse on Pennell's bird's-beak but the number of plants damaged generally appears to be minimal. Pennell's bird's-beak growing along roadsides is threatened by roadside maintenance such as mowing and spraying. The limited number and isolated condition of these populations make this species susceptible to extinction from random, catastrophic events.
Conservation and Recovery
Recovery of Pennell's bird's-beak must first focus on protecting and managing populations at the two remaining locations by working with the California Department of Fish and Game and private landowners to ensure long-term survival.
The California Department of Fish and Game developed a management plan for the Harrison Grade Preserve in 1987, and implementation is in progress. In 1995, a fence was built along the eastern edge of the preserve.
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
U.S. Fish and Wildlife Service. 1998. "Recovery Plan for Serpentine Soil Species of the San Francisco Bay Area." Portland, Oregon, 330+ pp.