No Common Name
|Listed||October 29, 1991|
|Description||Branched perennial with narrowly elliptic leaves and clusters of deeply notched, white flowers.|
|Habitat||Moist forest cliffs.|
|Threats||Alien plant species, low numbers.|
Silene perlmanii is a branched perennial in the pink family. A large number of stems rise from a woody base to a height of 12-20 in (30-50 cm). The narrowly elliptic leaves are 2-4 in (5-10 cm) long. A few deeply notched, white flowers are borne in clusters at the ends of the stems. S. perlmanii flowers in the spring, depending on climatic conditions. Flowers last for a day. Fruits develop in a few weeks. S. perlmanii, the only plant of the genus on the Hawaiian island of Oahu, can be distinguished from other Silene species by its white petals and by having a calyx, densely covered with short hairs, that is longer than 0.7 in (1.8 cm).
S. perlmanii grows on cliff faces in moist forest at an elevation of 2,600 ft (790 m). Associated species include laukahi kuahiwi (Plantago princeps ).
S. perlmanii was discovered in 1987 in the Waianae Mountains of Oahu. The only known population in 1993, located between Palikea and Pohakea Pass in the southern Waianae Mountains, consisted of 10-20 plants, but no individuals were known to survive in the wild as of December 1997.
The main threats to S. perlmanii are competition from non-native plant species and the low number of known individuals. Almost all native Hawaiian flora are in competition with aggressive alien species, and S. perlmanii is threatened by several. Christmas berry forms dense thickets and may also release chemicals that inhibit the growth of other species. Firetree was planted in the Waianae Mountains during a reforestation project; besides forming a dense closed canopy that excludes other species, it produces its own nitrogen, enabling it to colonize areas to which native species have become adapted. Molasses grass grows in dense mats that smother native vegetation.
S. perlmanii is very vulnerable to extinction through unpredictable human or natural events, and the species may already have become extinct in the wild.
Conservation and Recovery
S. perlmanii is being propagated at the Lyon Arboretum and the National Tropical Botanical Garden. Appropriate habitat in historical locations in the Waianae Mountains needs to be located so that propagated plants can be used to establish a wild population. The Nature Conservancy of Hawaii has constructed a fence around the 90-acre (36-hectare) site where the species was last seen in order to minimize the impacts of feral animals and alien plants, and this enclosure may provide suitable habitat for the regeneration of the species.
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 Pacific Remote Islands Ecological Services Field Office
300 Ala Moana Blvd., Room 3-122
P.O. Box 50088
Honolulu, Hawaii 96850-5000
Telephone: (808) 541-1201
Fax: (808) 541-1216
Cuddihy, L. W., and C. P. Stone. 1990. Alteration of Native Hawaiian Vegetation: Effects of Humans, Their Activities, and Introductions. Cooperative National Park Resources Study Unit, University of Hawaii Press, Honolulu.
Culliney, J. L. 1988. Islands in a Far Sea: Nature and Man in Hawaii. Sierra Club Books, San Francisco.
Stone, C. P., and J. M. Scott, eds. 1985. Hawai'i's Terrestrial Ecosystems: Preservation and Management. Cooperative National Park Resources Study Unit, University of Hawaii Press, Honolulu.
Wagner, W. L., D. R. Herbst, and S. H. Sohmer. 1990. Manual of the Flowering Plants of Hawai'i'. University of Hawaii Press and Bishop Museum Press, Honolulu.