Haha

Cyanea grimesiana ssp. obatae

Description

Cyanea grimesiana ssp. obatae is a shrub in the bellflower family, usually unbranched, that grows to a height of 3.3-10.5 ft (1.0-3.2 m). Its leaves, 10.5-23 in (0.3-0.6 m) long by 5.5-12.5 in (14.0-31.8 cm) wide, are deeply cut into nine to 12 lobes per side. The plant usually has small pickles on its stem and leaves. Clusters of six to 12 stalked flowers arise from the leaf axils. Sepals are fused to the ovary, forming a cup 0.3-0.6 in (7.6-15.2 mm) long with small, narrow, triangular lobes at the tips. The petals are purplish or greenish to yellow-white, often washed or striped with magenta, and are about 2-3 in (5.1-7.6 cm) long by 0.2-0.4 in (5.1-10.2 mm) wide. Fruits are elliptical orange berries 0.7-1.2 in (1.8-3.0 cm) long. This species is distinguished from the other two subspecies by its short, narrow calyx lobes that are not fused or overlapping. C. grimesiana ssp. obatae flowers and fruits year round, depending on rainfall.

Habitat

C. grimesiana ssp. obatae typically grows on steep, moist, shaded slopes in diverse mesic to wet forests at an elevation of 1,800-2,200 ft (549-671 m). Associated plants include mamaki, papala kepau, kukui, and various ferns.

Distribution

Historically, C. grimesiana ssp. obatae was known in the southern Waianae Mountains from Puu Ha-papa to Kaaikukai, a distance of about 4 mi (6.4 km).

The three extant populations, 4 mi (6.4 km) apart on Federal and private land, contained 13 individuals in 1997—Kaluaa had four plants, Ekahanui had eight, and North Palawai had one.

Threats

The major threats to C. grimesiana ssp. obatae are competition from alien plants such as Koster's curse, kukui, and Christmasberry; habitat degradation by feral pigs; predation of seeds or fruits by introduced slugs and rats; damage to flowers and stems of plants by rats; damage by the two-spotted leafhopper; risk of extinction due to naturally occurring events; and reduced reproductive vigor due to the small number of living individuals.

Conservation and Recovery

The Nature Conservancy of Hawaii fenced the population of eight plants in Ekahanui Gulch and is controlling alien weeds and monitoring this population. Field crews count and map plants and gather basic phenological data.

The Division of Forestry and Wildlife is growing 19 individuals of C. grimesiana ssp. obatae at the mid-elevation Nike missile site in the Walanae Mountains, with 10 individuals ready for planting in The Nature Conservancy of Hawaii preserve at Honouliuli. This species is also being successfully propagated at the National Tropical Botanical Garden and the Lyon Arboretum.

The only population that is fenced is Ekahanui Gulch. Efforts should be made to fence and manage the remaining two extant populations at Kaluaa and North Palawai. Subsequent control or removal of pigs from these areas will alleviate their impact on native ecosystems. A commitment should be developed for long-term stewardship and conservation of these areas once they have been enclosed. Specific efforts should be made to immediately weed and protect all extant populations.

The three populations of C. grimesiana ssp. obatae on Oahu are seriously threatened by rat predation. A rat control plan should be developed and implemented. This should include the use of the currently approved diphacinone bait blocks and ultimately a more broad-scale method such as aerial dispersal of rodenticide.

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

Senior Resident Agent Office
U.S. Fish and Wildlife Service
300 Ala Moana Boulevard, Room 7-235
P.O. Box 50223
Honolulu, Hawaii 96850-5000
Telephone: (808) 541-2681
Fax: (808) 541-3062

Reference

U.S. Fish and Wildlife Service. 27 June 1994. "Endangered and Threatened Wildlife and Plants: Endangered Status for Three Plants from the Waianae Mountains, Island of Oahu, HI." Federal Register 59 (122): 32932-32938.