San Clemente Island Indian Paintbrush

Castelleja grisea

Description

San Clemente Island Indian paintbrush, Castelleja grisea, is an erect, leafy, shrubby perennial with a woody, many-branched stem. Leaves grow in an alternate pattern along the stems, are entire (without toothed or lobed edges), and measure up to 1.2 in (3 cm) long. Flowers have dull yellow pistils and green bracts. This species appears to be parasitic, taking nourishment from the roots of other plants.

Habitat

San Clemente Island Indian paintbrush is found in canyons beneath the rocky cliffs and on island beaches among boulders. Often plants are mixed with cacti, particularly on slopes accessible to goats. This distribution may represent a refuge rather than preferred habitat. When the island was surveyed in 1984, a colony was discovered at the southern end of the island on relatively flat, open terrain. Its presence here suggests that this Indian paintbrush may have enjoyed a more widespread occurrence on the island before feral goats denuded much of the vegetation. The habitat elevation ranges from sea level to about 1,000 ft (300 m).

Distribution

This species is endemic to San Clemente Island, one of the larger California Channel Islands. The rugged island is situated 64 mi (102 km) west-northwest of San Diego and about 90 mi (140 km) due south of Los Angeles.

The species occurs in small numbers over most of the island, but appears to be more common in rocky areas that are not heavily grazed. The estimate of the total population in 1984 was about 1,000 plants, with the largest group at Pyramid Point.

Threats

Browsing wild goats trample and damage plants, particularly seedlings, and may prevent development of the specialized root structures that allow the plant to parasitize its host species. Future studies may show how this host dependency affects the plant's distribution. Military activities on the island, such as construction of utility buildings and extensive practice bombing, have undoubtedly impeded the paintbrush's growth.

Conservation and Recovery

Restoration of this plant will involve a general program of recovery for its host plant species, requiring removal of introduced plants and feral animals. All marginal, sparsely vegetated land along cliff sides and among boulders is now considered essential habitat for paintbrush, and efforts have been initiated to control erosion, which is particularly severe in some places. Areas of suitable habitat are being cleared of introduced plants, and indigenous plants, including the paintbrush, are being reintroduced. A healthy nursery stock and seed collected from the plants over the last few years is providing plants for the reintroduction effort.

Contact

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/

References

Dunkle, M. B. 1941. "New Plants from the Channel Islands of California." Southern California Academy of Science Bulletin 40:107-108.

U. S. Fish and Wildlife Service. 1984. "Recovery Plant for the Endangered and Threatened Species of the California Channel Islands." U. S. Fish and Wildlife Service, Portland.