'Oha Wai (Clermontia peleana)

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'Oha Wai

Clermontia peleana

ListedMarch 4, 1994
FamilyCampanulaceae (Bellflower)
DescriptionTall shrub with alternate, stalked, oblong, toothed leaves; and blackish purple or greenish white petals.
HabitatMontane wet forests dominated by koa (Acacia koa ), 'ohi'a (Metrosideros collina ) and/or tree ferns.
ThreatsHabitat disturbance caused by feral pigs and illegal cultivation of Cannabis sativa, roof or black rat damage, flooding, and stochastic extinction.


This 'oha wai, Clermontia peleana, of which there are two subspecies, is a shrub or tree 5-20 ft (1.5-6m) tall, which does not root in soil and grows on the plants 'ohi'a, koa, and ama'u's. The alternate, stalked, oblong or oval toothed leaves reach a length of 3-8 in (7.5-20.3 cm) and a width of 1.2-2 in (3-5 cm). Flowers are single or paired, each on a stalk 1.2-1.8 in (3-4.6 cm) long with a main stalk 0.3-0.7 in (0.8-1.8 cm) long. Five small green calyx lobes top the hypanthium. The blackish-purple (ssp. peleana ) or greenish-white (ssp. singuliflora ) petals are 2-2.8 in (5-7 cm) long and 0.3-0.5 in (0.8-1.3 cm) wide. They are fused into a one-lipped, arching tube with five down-curved lobes. Berries of spp. peleana are orange and 1-1.2 in (2.5-3 cm) in diameter. Berries of spp. singuliflora are unknown. This species is distinguished from others of the genus by its epiphytic growth habit; its small, green calyx lobes; and its one-lipped, blackish-purple or greenish-white corolla.


This species typically grows epiphytically in montane wet forests dominated by koa (Acacia koa ), 'ohi'a (Metrosideros collina ) and/or tree ferns at elevations between 1,740 and 3,800 ft (530 and 1,158 m). Associated species include 'olapa, kolokolo mokihana, and naupaka kuahiwi (Scaevola gaudichaudii ).


Historically, C. peleana ssp. peleana has been found on the island of Hawaii on the eastern slope of Mauna Loa and the northeastern and southeastern slopes of Mauna Kea.

C. peleana spp. singuliflora was formerly found on the island of Hawaii on the northern slope of Mauna Kea and on East Maui on the northwestern slope of Haleakala, but the subspecies has not been seen in either place since the early part of the twentieth century and is believed to be extinct.

Today, this species is known near Waiakaumalo Stream; by the Wailuku River; near Saddle Road; and between the towns of Glenwood and Volcano on the eastern side of the Big Island. The four known populations, which extend over a distance of about 12 by 5 mi (19.3 by 8 km), are located on state and federally-owned land, and contain a total of approximately eight known individuals.


Major habitat destruction resulting from ungulates, particularly pigs, is a primary cause of the decline of this taxon. Cultivation of Cannabis sativa (marijuana) has also disturbed areas which might be suitable habitat for C. peleana ssp. peleana. Roof or black rats may limit fruit production. Loss of pollinators may limit C. peleana ssp. peleana 's reproductive capability, making recovery difficult or impossible; however, little information is available regarding the relationship between C. peleana ssp. peleana and nectar-feeding birds and/or other suitable pollinators. Natural events such as fire and flooding may severely inhibit the survivability of the taxon.

Small numbers of individuals and the scattered distribution of populations are significant threats, not only because they limit the gene pool and further depress reproductive vigor, but also because a single natural or human-induced disturbance may be catastrophic and lead to the extirpation of the taxon. Unwarranted visits by humans could adversely impact the populations.

Conservation and Recovery

Volcano Rare Plant Facility germinated one individual from seed acquired in 1992. The National Tropical Botanical Garden (NTBG) has germinated seeds and propagated the taxon. Lyon Arboretum has been successfully cloning C. peleana ssp. peleana using leaf tissue and has about 300 plants in the greenhouse. There have been no attempts to out-plant the taxon at this point because these clones are not considered representative of the population and thus not useful for conservation purposes.

In order to prevent possible extinction of this taxon, maintenance of ex situ (at sites other than the plant's natural location, such as a nursery or arboretum) genetic stock is necessary. The eight known plants should be protected from ungulates, particularly pigs, via fencing or other means. Propagation and outplanting of ex situ stock will likely be needed in order to establish a sufficient number of plants for recovery within the taxons's four known locations, and a fifth population will need to be established.


Pacific Joint Venture
300 Ala Moana Blvd., Rm. 3-122
Honolulu, Hawaii 96850-0056
Telephone: (808) 541-2749
Fax: (808) 541-2756

U.S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Complex
911 N.E. 11th Avenue
Portland, Oregon 97232-4181
Phone: (503) 231-6121


U.S. Fish and Wildlife Service. 4 March 1994. "Endangered and Threatened Wildlife and Plants; Determination of Endangered or Threatened Status for 21 Plants from the Island of Hawaii, State of Hawaii." Federal Register 59 (43): 10305-10325.

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'Oha Wai (Clermontia peleana)

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