Haha (Cyanea glabra)

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Haha

Cyanea glabra

StatusEndangered
ListedSeptember 3, 1999
FamilyCampanulaceae (Bellflower)
DescriptionA tropical shrub.
HabitatNative tropical forest.
ThreatsHabitat destruction, introduced mammalian herbivores, non-native slugs, invasive alien plants.
RangeHawaii

Description

The haha is a branched shrub. The leaves of juvenile plants are deeply lobed, while those of adult plants are more entire and elliptical. Adult leaves are 9-14 in (23-36 cm) long and 3-5 in (7-12 cm) wide. The upper surface of the leaves is green and hairless, while the lower surface is pale green and hairless to sparsely hairy. The margins of mature leaves are thickened and shallowly toothed to irregularly lobed. The flowers are borne in an inflorescence of six to eight, supported by a peduncle (inflorescence stalk) 0.8-2.2 in (20-55 mm) long. The hypanthium is 0.3-0.4 in long (7-10 mm), up to 0.2 in (5 mm) wide, and widest at the top. The corolla (petals) is white, often with a pale lilac tinge, and is 2-2.4 in (50-60 mm) long and about 0.3 in (8 mm) wide. The tube of the corolla is curved, and the lobes are spreading, up to one-third times as long as the tube, and covered by small, sharp projections. The ripe berries are 0.4-0.6 in (10-15 mm) long, elliptical, and colored yellowish orange. The calyx (sepals) persists on the berry. This species is differentiated from others in this endemic Hawaiian genus by the size of its flowers and the deeply lobed juvenile leaves.

Habitat

The habitat of the haha is wet tropical forest dominated by koa (Acacia koa ) and/or o'hia (Metrosideros polymorpha ). It occurs at elevations between 3,200 and 4,400 ft (975 and 1,340 m).

Distribution

The haha is a locally evolved, or endemic species that is only known from the island of Maui, Hawaii. The Hawaiian archipelago has an extremely large fraction of endemic species; about 89% of the indigenous flowering plants occur nowhere else in the world. The haha is historically known from two locations on West Maui and five on Haleakala, East Maui.

Threats

The primary threat to the haha is destructive herbivory by introduced species of slugs. It is also affected by habitat degradation and destruction by feral pigs, flooding, and competition with several introduced species of invasive plants, including the shrub strawberry guava (Psidium cattleianum ), the Koster's curse (Clidemia hirta ), and other non-native plants. Introduced rats are also probably herbivores of this plant, as may be the non-native two-spotted leafhopper (Saphonia rufofascia ). Because of its limited range and small population size, the haha is also potentially threatened by catastrophic events of weather, wildfire, or other disturbances. There are only two surviving populations of the haha. One population consists of only 12 individuals in Kauaula Gulch on West Maui on privately owned land, and another contains a scattered population of about 200 individuals in Kipahulu Valley, within Haleakala National Park.

Conservation and Recovery

The major surviving population of the haha is located within Haleakala National Park, which is managed to conserve its indigenous biodiversity. The other, smaller population is on private land, and is potentially at risk from disturbance or other human actions. Conservation of the endangered haha requires that all of its remaining critical habitat be protected and managed to reduce the threats posed by non-native herbivores and competitors. The populations of the haha should be monitored against further change, and research undertaken to develop a better understanding of degrading influences faced by the endangered plant, and ways of mitigating those effects.

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
(503) 231-6121
http://pacific.fws.gov/

U. S. Fish and Wildlife Service, Pacific Islands
Ecoregion, Pacific Islands Fish and Wildlife Office
300 Ala Moana Boulevard, Room 3-122
P. O. Box 50088
Honolulu, Hawaii 96850
Telephone: (808) 541-3441
Fax: (808) 541-3470

Reference

U.S. Fish and Wildlife Service. 3 September 1999. "Endangered and Threatened Wildlife and Plants: Final Endangered Status for 10 Plant Taxa From Maui Nui, Hawaii." Federal Register 64(171): 48307-48324.

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Haha (Cyanea glabra)

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