Haha (Cyanea st.-johnii)
|Listed||October 10, 1996|
|Description||Unbranched shrub with a woody stem, smoothly toothed, thick leaf edges, and hairless white petals suffused with pale violet in the inner surface.|
|Habitat||Wet, windswept slopes and ridges in 'ohi'a mixed shrubland or 'ohi'a-uluhe shrubland.|
|Threats||Habitat degradation by feral pigs and hikers, potential predation by rats, and competition with Koster's curse.|
Cyanea st.-johnii (haha) is an unbranched shrub of the bellflower family with a woody stem 12-24 in (30-60 cm) long. The leaves are lance-shaped to inversely lance-shaped, 2.4-5.1 in (6.1-13.0 cm) long, and 0.6-0.8 in (1.5-2.0 cm) wide. The smoothly toothed leaf edges are thickened and curl under. A flowering stalk between 0.2 and 0.6 in (0.8 and 1.5 cm) in length supports 5 to 20 flowers. The white petals, hairless and suffused with pale violet in their inner surfaces, are 1.2-2.4 in. (3.0-6.1 cm) long. Cyanea st.-johnii is distinguished from others in its endemic Hawaiian genus by the length of the leaves, the distinctly curled leaf margins, and the petal color. This species has been observed in flower in July through September.
Edward Hosaka, who collected a new lobelioid while hiking in the Koolau Mountains of Oahu, later described and named it Rollandia st.-johnii in 1935. Rollandia st.-johnii var. obtusisepala, named by Wimmer 1953, is not recognized in the most recent treatment of Hawaiian members of the family. Lammers and others published the new name Cyanea st.-johnii in 1993 when they merged Cyanea and Rollandia. The specific epithet honors the late Harold St. John.
Cyanea st.-johnii typically grows on wet, windswept slopes and ridges from 2,260-2,800 ft. (690-850 m) elevation in 'ohi'a mixed shrubland or 'ohi'a-uluhe shrubland. Associated plants include naupaka kuahiwi, uki, kookoolau, kamakahala, naenae, kopiko, hapuu, kanawao, maile, hame, and Freycinetia arborea (ieie).
Cyanea st.-johnii was known historically from 11 populations in the central and southern Koolau Mountains of Oahu. Six extant populations contained between 40 and 50 total plants in 1997: less than 10 individuals at Waimano Trail summit to Aiea Trail summit, four at the summit ridge crest between Manana and KipaPa trails, 15 between the summit of Aiea and Halawa trails, one at Summit Trail south of Poamoho cabin, six at Wamano ridge between North and North central Waimano and 12 at Wailupe-Waimanalo summit ridge. These populations are found on City and County of Honolulu, state, and private, lands.
Cyanea st.-johnii is threatened by habitat degradation and destruction by feral pigs, potential predation by rats, competition with the noxious alien plant Koster's curse, and risk of extinction from naturally occurring events or through reduced reproductive vigor due to the small number of remaining populations and individuals. The plants between the summit of Aiea and Halawa Trail also are threatened by trampling by hikers.
Cyanea st.-johnii is potentially threatened by feral pig predation; pigs favor plants from the bellflower family for food, and this species is not known to be unpalatable to rodents.
It is possible that rats eat the fruit of Cyanea st.johnii.
The noxious shrub Koster's curse is also a threat to this listed species.
Overcollection for scientific or horticultural purposes and excessive visits by individuals interested in seeing rare plants in their native situations could seriously damage Cyanea st.-johnii, whose populations are close to trails and roads and therefore easily accessed by potential collectors.
Cyanea st.-johnii has populations in recreational areas, near trails, and close to roads, making it very vulnerable to general human disturbance.
Conservation and Recovery
A Recovery Plan for the haha and associated species was published by the Fish and Wildlife Service in 1998. It survives in only five known populations, and these must be rigorously protected from environmental threats. Its critical habitat must be managed to reduce the damage caused by pigs and rats. This could be done by enclosing the plants in secure fencing, or by reducing or eliminating the non-native mammals. The abundance of alien invasive plants must also be reduced in the habitat of the haha. Hiking trails must also be located away from the critical habitat of the rare plant. The populations of the haha should be monitored, and research undertaken into its biology and habitat needs, with the aim of developing management practices appropriate to maintaining or enhancing its habitat.
U. S. Fish and Wildlife Service
Pacific Island Ecoregion
300 Ala Moana Boulevard, Room 3108
P.O. Box 5088,
Honolulu, Hawaii 96850
Telephone: (808) 541-3441
Fax: (808) 541-3470
U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Building
911 N. E. 11th Ave.
Portland, Oregon 97232-4181
Telephone: (503) 231-6121
U.S. Fish and Wildlife Service. 10 October 1996. "Endangered and Threatened Wildlife and Plants; Determination of Endangered Status for Twenty-five Plant Species From the Island of Oahu, Hawaii." Federal Register 61 (198) 53089-53108.
U.S. Fish and Wildlife Service. 1998. "Recovery Plan for Oahu Plants." U.S. Fish and Wildlife Service, Portland, Oregon.